Electronics 1961-12-29: Vol 34 Iss 52

December 29, 1961

electronics

A McGraw-Hill Publication 75 Cents

Photo at right
SONAR FOR
FROGMEN

Locates
underwater
objects, p 37

MICROCIRCUIT
‘SLIDE RULE’

Molecular circwut
multiplies and
divides, p 40

DIGITAL
TRACKING
Keeps radar

locked on
target, p 46

CAMERA
PERISCOPE
For cathode-

ray-tube : = HOIR SOGuY NNV

‘ bie pane 4 — LS iSuId 8 ¢I¢
photography, p 51 . c ey Ld2@ WIuor 0"

Sy we eee PRs EE

1000-Mc Standard K&S

Short-term and long-term stabilities comparable to the best crystal
controlled standards available . . . at less than 24 the price!

Outputs from 100c to 1000 Mc at decade intervals, plus 60c, 400c,
and 5 Mc... more outputs than any other commercial unit provides.

Two big reasons why
you get so much for so little money in
a G-R Frequency Standard:

7 NO militarization .. . why pay more for extreme shock
and fungus protection — it doesn’t make a standard more
stable nor does it contribute to laboratory usefulness.

2 Years of experience . . . this standard’s ancestors include
the first commercially-available crystal-controlled pri-
mary frequency standard.

5-Mc fifth-overtone crystal and

Long-term Stability: 5 parts in 10'® per day,
two-stage oven.

averaged over 10 days after 60 days

; : , operation.
Short-term Stability: 1 part in 10! per min.,

using 1-sec samples. Syncronometer resolution is better than
+0.2 msec for time comparisons consist-
ent with stability of sky-wave signals from
WWYV and other stations.

Harmonics for measurements well be-
yond X-band can be produced.

oe from 100¢ to 1000 Mc at decade 10-kc and 100-kc square wave available for
re triggering purposes.
Low Noise: pulse-type dividers give fail-

safe operation and minimize phase noise
below 5 Mc; phase-locked crystal oscilla-
tors provide clean signals above 5 Mc —

Emergency Power Supply available as an
accessory.

Optional Plug-in Units provide 400- and

f-m noise less than 1 part in 10°. 60-cycle outputs.

Type 1120-AH 1000-MC Frequency Standard... $6450 complete

Includes, from top to bottom, 1103-B Syncronometer . . . $900
1113-A Standard Frequency Oscillator . . . $1550

1114-A Frequency Divider . . . $950

1112-A Standard Frequency Multiplier (1,10,100 Mc) . . . $1450
1112-B Standard Frequency Multiplier (1000 Mc) . . . $1360
plus rack and all interconnection provisions.

also available for

automatic frequency measurement
1130-A Digital Time and Frequency Meter
“The Counter With A Memory”’.

Oe ee mn ne Ae

Write for information regarding
a system for frequency measurements
to one part in 10!'.

GENERAL RADIO COMPANY

WEST CONCORD, MASSACHUSETTS

WEW YORK, WOrth 4-2722 CHICAGO PHILADELPHIA
‘ in Ri ; Oak Park Abington
District Office in Ridgefield, N. J.
7 yeh os Village 8-9400 HAncock 4-7419

WASHINGTON, D.C. SYRACUSE SAN FRANCISCO
Silver Spring Syracuse Los Altos
JUniper 5-1088 GLenview 4-9323 WHitecliff 8-8233

LOS ANGELES ORLANDO, FLA. IN CANADA
Los Angeles Orlando Toront

0
HOllywood 9-6201 GArden 5-4671 CHerry 6-2171

December 29, 1961

electronics

A McGraw-Hill Publication 75 Cents

W. W. MacDONALD, Editor

J. M. CARROLL, Managing Editor
SENIOR EDITORS: Samuel Weber,
George W. Sideris. SENIOR ASSO-
CIATE EDITORS: William E. Bushor,
Michael F. Wolff. ASSOCIATE EDI-
TORS: Michael F. Tomaino, Sylvester
P. Carter, William P. O’Brien, John
F. Mason, Thomas Emma, Sy Vogel,
leslie Solomon, M. M._ Perugini,
George J Flynn, Laurence D.
Shergalis. ASSISTANT EDITORS:
Nilo Lindgren, Stanley Froud,
Stephen B. Gray, Roy J. Bruun,
George V. Novotny, Leon H. Dulberger.
REGIONAL EDITORS: Harold C. Hood
Pacific Coast, Los Angeles), Thomas
Maguire (New England, Boston),
Cletus M. Wiley (Midwest, Chicago).
ART DIRECTOR: Harry Phillips; Howard
R. Berry. PRODUCTION EDITOR: John
C. Wright, Jr. EDITORIAL ASSIST-
ANTS: Gloria J. Meurer, Bernice Duffy,
lorraine Rossi, Virginia T. Bastian,
Lynn Emery, Lavra W. Smith, Bette H.
Snyder, Rosemary Abbruzzese, Judy
Haskins.

JAMES GIRDWOOD, Publisher

Scuba diver walks from sea with sonar set that enables him to
locate objects in murky waters. Transistor unit has 120 yards

range. See p 37 COVER

ITERATIVE TECHNIQUES Widen Applications of Analog Com-
puters. New equipment exhibited at Eastern Joint Computer
Conference

Gondola Makes Dry Runs in Space. Simulator performs all phases
of manned space flight missions

Engineer Supply Drops Sharply. Demand is up, but fewer students
enroll in engineering colleges

Computer Controls Parking Garage. One attendant can get 27 cars
parked in 10 minutes

OSCAR SATELLITE Orbited by Amateur Radiomen. Group hopes
to build relay capability into future satellites

PORTABLE SONAR FOR FROGMEN. Uses audio tone as range
indicator. I. R. Colldeweih, E. L. Walls and R. D. Lee

MICROCIRCUIT SLIDE RULE Multiplies and Divides. Diodes and
transistors are fabricated on single silicon substrate. H. C. Lin,
C. E. Benjamin, P. W. Smith and B. S. Aronson

Illumination Stabilizer for Photosensing System. Transistors are
used in feedback loop. J. R. Dyke

DIGITAL TRACKING: Automatic Radar Ranging Control. Locks
fast to target and provides highly accurate data. D. L. Nepveux

Camera Periscope for Crt Photography. How to design optics for
display. D. Levine

Crosstalk Components and Materials
Comment Production Techniques
Electronics Newsletter New on the Market
Washington Outlook Literature of the Week
Meetings Ahead People and Plants

Research and Development Index to Advertisers

STRENGTH
IN THE

MIDDLE

e223 EY

Tarzian's new 6-amp silicon rectifier
strengthens your ability to select the
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requirement.

The new line-up gives you a wider
choice of units—2, 6, 10, 12, and 20-amp
—each delivering quality performance
at traditional Tarzian prices. Each unit
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to 420 maximum RMS voltage, in incre-
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You'll find additional specifications
spelled out in the new Tarzian catalog.
Free copies, and free application engi-
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2 CIRCLE 2 ON READER SERVICE CARD

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electronics

Arnold Pulse Transformer
Cores ate individually tested

under actual pulse conditions

Here’s
technical data on

ARNOLD
SILECTRON
CORES

Bulletin SC-107 A

. this newly-
reprinted 52-page
bulletin contains
design information on Arnold Tape Cores wound
from Silectron (grain-oriented silicon steel). It
includes data on cut C and E cores, and uncut
toroids and rectangular shapes. Sizes range from
a fraction of an ounce to more than a hundred
pounds, in standard tape thicknesses of 1, 2, 4
and 12 mils.

Cores are listed in the order of their power-
handling capacity, to permit easier selection to fit
your requirements, and curves showing the effect
of impregnation on core material properties are
included. A valuable addition to your engineering
files—write for your copy today.

ADDRESS DEPT. E-12

December 29, 1961

The inset photograph above illus-
strates a special Arnold advantage: a
10-megawatt pulse-testing installa-
tion which enables us to test-prove
pulse cores to an extent unequalled
elsewhere in the industry.

For example, Arnold 1 mil Silectron
“C” cores—supplied with a guaran-
teed minimum pulse permeability of
300—are tested at 0.25 microseconds,
1000 pulses per second, at a peak flux
density of 2500 gausses. The 2 mil
cores, with a guaranteed minimum
pulse permeability of 600, receive
standard tests at 2 microseconds, 400
pulses per second, at a peak flux

density of 10,000 gausses.

The test equipment has a variable
range which may enable us to make
special tests duplicating the actual
operating conditions of the trans-
former. The pulser permits tests at
.05, .25, 2.0 and 10.0 microsecond
pulse duration, at repetition rates
varying anywhere from 50 to 1000
pulses per second.

This is just another of Arnold's
facilities for better service on mag-
netic materials of all description.
@ Let us supply your requirements.
The Arnold Engineering Company,
Main Office & Plané, Marengo, Il.

wARNOLD

SPECIALISTS in MAGNETIC MATERIALS

BRANCH OFFICES and REPRESENTATIVES in PRINCIPAL CITIES
Find them FAST in the YELLOW PAGES

CIRCLE 3 ON READER SERVICE CARD

electronics
December 29, 1961 Volume 34 No. 52

a
Published weekly, with Electronics
Buyers’ Guide and Reference issue,
as part of the subscription, by
McGraw-Hill Publishing Company,
Inc. Founder: James H. McGraw
(1860-1948).

Title ® registered U.S. Patent Office;
Copyrighted © 1961, McGraw-Hill
Publishing Company, Inc. All rights
reserved, including the right to repro-
duce the contents of this publication,
in whole or in part.

Executive, editorial, circulation and
advertising offices McGraw-Hill Build-
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36, N. Y. Telephone Longacre 4-3000.
Teletype TWX N.Y. 1-1636. Cable
McGrowhill, N. Y. PRINTED IN AL-

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paid.

OFFICERS OF THE PUBLICATIONS DI-
VISION: Nelson L. Bond, President;
Shelton Fisher, Wallace F. Traendly,
Senior Vice Presidents; John R. Calla-
ham, Vice President and Editorial Di-
rector; Joseph H. Allen, Vice President
ond Director of Advertising Sales; A.
R. Venezian, Vice President and CLircu-
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OFFICERS OF THE CORPORATION:
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Kelly, Harry L. Waddell, Executive
Vice Presidents; L. Keith Goodrich,
Executive Vice President and Treas-
vrer; John J. Cooke, Vice President
and Secretary.

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change to become effective.

Postmaster: Please send Form 3579
to Fulfill t M ger, Electronics,
330 West 42nd Street, New York 36,

New York.

©:

Audited Paid Circulation

CROSSTALK

Shakeup, Not Shakeout

WE’RE WONDERING what happened to the big shakeout in the
electronics industry that so-called experts have been predicting
for the past couple of vears. As this vear winds up and the
reports come in we still don’t see this major holocaust.

We see changes in technology. We see new patterns of sales
and distribution. We see new markets opening up. The sight of
the nation’s cities littered with the corpses of electronics com-
panies, however, is something we don’t see... nor do we expect to.

Against this bullish attitude, adequately bolstered from within
our industry, we do see areas where glamor dazzled reason. This,
however, has been on a small scale in terms of the entire industry.

In all likelihood, fingers that were burned would have gotten
that way had they been handling electronics, apple pies or costume
jewelry.

We cannot, from anything we know, extrapolate a picture of
companies falling by the wayside in droves. The declines within
the electronics industry derive from changing technology.
What some observers-from-without fail to realize is that tech-
nological improvement does not create voids. It fills needs. For
each category of equipment that declines from the market, a new
category or class of categories comes into being.

The manufacturer sensitive to the changing technologies of
this industry will change with it and prosper. The inflexible
management, seeing no view but the one immediately before it,
will bulldog its way to oblivion and not be missed by the industry
at large.

The more doomsday predictions we hear about the electronics
industry the more we recall Mark Twain’s quip following the
mistaken appearance of his obituary in a small town newspaper.
“The reports of my death have been grossly exaggerated !”

Coming In Our January 5 Issue

SUMMING UP. For several years, throughout the industry, U. S.
our way of editorially greeting and foreign government officials.
the new year has been to take a Finally, they condensed the facts
long-range look at electronics into 32 pages and picked an ap-

market opportunities. This year,
we assigned four men—backed
up by our regional editors—to
hunt up fresh, authoritative sta-
tistics, evaluation and _ predic-
tions. They used the News Sys-
tem (North, East, West, South),
contacting top executives

propriate title, “Our Growing
Markets.”” Appropriate because
they found that wide-awake com-
panies with a talent for research,
development and production will
find many opportunities for new
products and bigger sales in the
years ahead.

electronics

“Is that
the new
Norton

You bet it is!

It’s dog-eared and marked up because
it’s in constant use by men who want
better materials — high purity refractory
materials which will stand up under the
most extreme thermal, mechanical, chem-
ical, electrical, and radioactive conditions.

This valuable, well-illustrated reference
describes in detail the many Norton re-
fractory materials which are helping to
solve widely different product and proc-
essing problems. Uses range from aiding

December 29, 1961

eZ
Ll

chemical reactions to stopping neutrons,
handling molten metals, protecting rocket
engines — and taming lightning.

Catalog lists physical, chemical and
electrical properties of CRYSTOLON* Sili-
con Carbide, ALUNDUM* Aluminum Oxide,
MAGNORITE* Magnesium Oxide, NORBIDE*
Boron Carbide, and Fused Zirconia. It’s
thought-provoking...areal “idea-starter!”

You may well profit from this book in
solving your own processing problems.
No charge or obligation, of course, write
for “Norton Refractory Grain,”

NorRTON ComPANY, Refractories Division,
692 New Bond St., Worcester 6, Mass.

*Trade-Marks Reg. U.S. Pat. Off. and Foreign Countries

(NoRTONy

REFRACTORIES
Crystallizing ideas
into products

CIRCLE 5 ON READER SERVICE CARD

¥ a SSeS BES
&

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PIEZO-
ELECTRIC
CERAMIC
ELEMENTS

ELEMENTS
FOR ALL
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= AS WELL AS
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TRANSDUCER ASSEMBLIES
FOR MOST APPLICATIONS,
SUCH AS UNDERWATER
SOUND AND
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Sprague-developed mass cauhidaties
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permit prompt production in a full,

wide range of sizes and shapes.
Look to Sprague for today’s most
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YOUR INQUIRIES

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SPRAGUE ELECTRIC COMPANY

35 Marshall Street, North Adams, Mass.

SPRAGUE

THE MARK OF RELIABILITY

CIRCLE 6 ON READER SERVICE CARD

COMMENT

Proprietary Rights

I want to congratulate you on
the excellent editorial on proprie-
tary rights that appeared in the
Oct. 27 issue (p 98).

I have personally been faced with
this problem on a good many occa-
sions, particularly when I was with
Aircraft Radio Corporation. I think
one point that I might add, that
possibly has not been stressed
enough in your editorial or other
articles on this subject, although it
is usually mentioned, is that a sup-
plier of electronic equipment to the
military must assume that the mili-
tary will need drawings and speci-
fications for certain replacement
parts in order to catalog them prop-
erly. They will also need informa-
tion for the maintenance and over-
haul of the equipment and this
means that a certain minimum
number of drawings and specifica-
tions must be supplied, whether the
manufacturer wants to or not.

The manufacturer cannot assume
that the equipment is to be deliv-
ered and then be forgotten about

Transistor Circuit Design

forever. If arrangements can be
made with the Contracting Officer
to supply specific drawings for the
above purposes only, I think the
manufacturer will have done his
duty and the military will have re-
ceived all the information that they
really need for operation and main-
tenance.
A. W. PARKES, JR.
President
Ballantine Laboratories, Inc.
3oonton, New Jersey

Plasma Engineering

I think your articles [p 47, July
14; p 33, Aug. 4; p 29, Sept. 1]
gave a concentrated but compre-
hensive picture of current plasma
physics research. The outlook for
industrial plasma research in the
U. S. was especially interesting.

In Uppsala, our work on low-
inductance capacitors and very fast
discharges continues. We will keep
you informed about results.

LARS HOGBERG
Fysiska Institutionen
Uppsala, Sweden

In the Nov. 3 issue (p 48) there were errors in the article, Computer-

Derived Curves Simplify Transistor Circuit Design,

Martin.

In the sentence following Eq. 7 (p 49), change R,/R,

by D. McLarin, of

= $to R,/R, = &

Graph F (p 50) should be labeled R,/R, = 3, rather than R,/R, =

In Eq. 17 (p 51), Z,,

is stated incorrectly.

One term of the numerator

is missing, and part of the denominator is placed above Eq. 18 in the
next column, Equations 17 and 18 should be as follows:

Zin —

tRin
R, + Rin

ty = te zs

The sentence following Eq.

igh Ry (1 + joC rs) + Riley (1+ Be)
RiR2 (1 + jwCeR;) + (Ri + R2) [Rs (1 + 8) + hie 1 + joCrRs))

(17)

(18)

30 (p 54) should be: Substituting Eq. 17

and 1/eC, in Eq. 30, rather than 1/oC.,,.
Equations 31 and 32 (p 54) will be in error due to the error in Eq. 17.
Equations 31 and 32 should be as follows:

1 RiRz thie + wCrlishie + Ra VL + B2)}

(31)

wl, RyR2(1 + wR» + (R, + RD IR: 1 + fe) + hie 1 + @CoRs)]

co. — Riles (1 + wCoRs) + (Ri 4
Seni

Equation 34 (p 54) should be

] Rihie

we Ra + Ris

The Martin Company
Orlando, Florida

- Rs) [Rs (A + 2) +h; e(l + wR) |
wR, R. [hie + wl "2Rshie + R; (i + Bo )}

(32)

STANLEY C. LOGAN
Information Services

electronics

10,000 VARIATIONS...

all stamped with the T-MARK of total reliability

Other spring fasteners may Jook like Tinnerman SPEED NUTS. But only those stamped with
the T-mark really are SPEED NuTs, made to Tinnerman’s high, precise standards of
reliability. Tinnerman quality controls are the most stringent in the industry. And only
Tinnerman stocks a half-billion SPEED NuTS... is tooled to turn out 10,000 variations

... develops 25 new designs each week. Protect your product’s good name by insist-
ing on genuine SPEED Nuts. Stamped with the Tinnerman “T”—the mark of total
reliability. Tinnerman Products, Inc., Department 12, Box 6688, Cleveland 1, Ohio.

CANADA: Dominion Fasteners Ltd., Hamilton, Ontario. T j N i E oa M A a

GREAT BRITAIN: Simmonds Aerocessories Ltd., Treforest, Wales.
FRANCE: Simmonds S.A., 3 rue Salomon de Rothschild, Suresnes (Seine).

Cra, iy Vi @
aS WOO jj ‘), V,/]
GERMANY: Mecano Simmonds GMBH, Heidelberg. CYQ266 / CLL)

Look for the Tinnerman “T”

December 29, 1961 CIRCLE 7 ON READER SERVICE CARD

MEASURE

VOLTAGE
to 500 KC

WITH YOUR

DC

VOLTMETER

electronics

NEW @ 457A AC TO DC CONVERTER

New ® 457A AC to DC Converter lets you inexpensively measure
ac voltage, 50 cps to 500 KC, with the ease and high resolution of
a dc digital voltmeter.

The average-responding 457A permits ac measurements to +0.3%
of reading +0.001 v to 50 KC and +0.75% +0.001 v to 500 KC.
This accuracy permits you to read ac voltages on a dec digital volt-
meter (such as the # 405BR/CR) with three digits resolution.

Waveform errors are minimized by this new converter. The dc
output of the 457A is always between 0 and 1 volt for up to full
scale input. Full scale is selected manually in decade ranges. Your
measurement convenience is further increased with overranging
by more than 2 to 1 and an input impedance of 1 megohm.

The 457A Converter can be used with an # 560 Series Digital Re-
corder, plus a digital voltmeter, to provide a permanent printed
record. Either the 457A analog or digital voltmeter output data
is suitable for other data logging equipment. The digital data may
be transferred, for example, to card or tape punches.

New ® instrument modular packaging permits easy stacking of
instruments on the bench, and simple conversion to rack mount.

Specifications

input Range: 0 to 300 v rms, in 4 decade ranges cor-
responding to 1, 10, 100 and 1,000 v
rms full scale.

50 cps to 500 KC

+0.3% of reading +1 mv, 50 cps to 50
KC; +0.75% +1 mv, 50 KC to 500 KC.

0 to 1.0 v dc, responding to average
value of ac input, with output cali-
brated as rms value of sine wave.

Output Impedance: 10,000 ohms.

Input Impedance: 1 megohm, shunted by 30 pf.

Size: 16%4” wide, 3%” high, 1344” deep.

Weight, 12 Ibs.
$350.00

Frequency Range:
Accuracy:

Output:

Price:

@ DEPENDABLE AUTOMATIC DIGITAL VOLTMETERS

& 405BR/CR Digital Voltmeter

Ideal for use with the 9
457A AC to DC Converter,
the ® 405BR/CR Digital
Voltmeters feature auto-

matic ranging, simple touch-and-read measurement and bright,
clear readout. By using the # 405 in conjunction with the 457A,
you can read ac voltages on the 405 to three digits with an overall
accuracy of +0.4% of reading +0.001 v to 50 KC, +0.75% of
reading +0.002 v to 500 KC. The ® 405BR and CR are identical
except that the 405CR includes (a) provision for external sam-
pling command, (b) digital recording outputs, plus (c) reading
hold-off capability, (d) print command when overranging, and
(e) remote readout outputs.

Specifications

Ranges: 0.001 to 999 v dc, 4 ranges.
Presentation: 3 significant figures, polarity indicator.
Accuracy: +0.2% of reading +1 count.
Ranging Time: 0.2 sec to 2 sec.
input Impedance: 11 megohms to dc, all ranges.
Response Time: Less than 1 sec.
AC Rejection: 3 db at 0.7 cps; min. 44 db at 60 cps.
Size: 7” high, 19” wide, 13%” deep

behind panel. Weight, 26 Ibs.

Price: @ 405BR, $850.00; @ 405CR, $925.00.

FOR EVEN GREATER SYSTEMS FLEXIBILITY, USE DYMEC 2401

INTEGRATING DIGITAL VOLTMETER!

DY-2401 integrating Digital Voltmeter

Unique flexibility for simple and complex systems applications is
yours with the Dymec 2401 Integrating Digital Voltmeter, which
effectively eliminates the effects of noise and hum by reading the
average value of voltage applied over a definite, selected sample
period. Range, sample period and sample rate are externally pro-
grammable. Applications are further extended by the nature of
the 2401, actually a voltage-to-frequency converter, combined with
a 300 KC electronic counter.

Equally versatile in systems application is the Dymec Model 2410

Multi-Converter (not shown) , which converts ac volts, resistance

and dc volts to a proportional dc voltage with i volt nominal full-
scale output. $1,975.00.

Call your Hewlett-Packard /Dymec representative today for further
information or for a demonstration on your bench.

HEWLETT-PACKARD COMPANY

1091C Page Mill Road Palo Alto, California, U.S.A.
Cable “HEWPACK” DAvenport 6-7000

Field representatives in all principal areas

December 29, 1961

Specifications

DC Voltage Ranges: +0.1, 1, 10, 100, 1,000 v nominal
full scale.

0.05% nominal.

Greater than 0.01%/day, 1 v range
and above.

1 megohm on 1 v and higher ranges,
100,000 ohms on 0.1 v range.

$3,750.00.

Overall Accuracy:
Stability:

Input Impedance:

Price:

Data subject to change without notice.
Prices f.0.b. factory.

HEWLETT-PACKARD S. A.
Rue du Vieux Billard No.1 _ Geneva, Switzerland
Cable “HEWPACKSA” Tel. No. (022) 26. 43. 36

CIRCLE 9 ON READER SERVICE CARD

UNRETOUCHED PHOTOGRAPHS MAGNIFIED 424 TIMES

FLIP-FLOP GATE HALF-SHIFT REGISTER

“F" Element “G”" Element “S" Element

HALF-ADDER BUFFER COUNTER ADAPTER

“H" Element “B” Element “Cc” Element

are a compatible set of integrated digital
functional blocks in which transistors and

resistors are diffused via the Planar proc-
ess into a single, monolithic chip of silicon. This family of functional elements is sufficient to efficiently fabricate a com-
puter logic section. No other components are required.

They are designed to operate in a full military environment, over a temperature range of —55 degrees C to +125 degrees
C. When integrated into a computer, they will operate at 1 mc clock rates over the above temperature range.

Micrologic elements are designed primarily to permit highly reliable data processing logic at very low cost. They make
possible a simplified approach to the job and hence greatly reduce the lead time to the prototype computer.

The cost savings are to computer manufacturers and the computer user. The choice of the elements and the nature of
the package, are great factors in the tota! cost reduction associated with the reliability, maintainability, repairability, logis-
tics, and training.

The size reduction (one order of magnitude) gained with Micrologic is an important by-product of the main objectives of

the program.

EL eae
IMMEDIATE AVAILABILITY E™y
All 6 Micrologic elements are available now for immediate vol- - } FR Cc ei i LD

ume delivery. Contact your Fairchild Field Sales Office.

RE ERE SE:
90% COST REDUCTIONS SEMICONDUCTOR
IN LOGIC DESIGN & ASSEMBLY 545 WHISMAN ROAD, MOUNTAIN VIEW, CALIF.- YORKSHIRE 8-816] - TWX: MN VW CAL 853

° . i A DIVISION OF FAIRCHILD CAMERA AND INSTRUMENT CORPORATION
Micrologic elements can cut logic system design and assembly
costs up to 90%; space requirements up to 95%; power needs up
to 75%. These savings are made possible through simplified lay- GENERAL SPECIFICATIONS FOR MICROLOGIC ELEMENTS

outs, standard handlings of TO-5 type packages, fewer inter- Speed * 50 nsec. delay per stage for all

board connections, single clocks, one power supply. pecan ee mine

Power * 15 mW per node

PLANAR RELIABILITY FanOut « 5° over tomo. range of —55° C.
Fairchild Micrologic elements have been life tested for 1,000,000 Voltage -« mel + 30%

element operating hours at 125°C without a single electrical Package * 8 lead TO-5 type (.170 height)
failure. The Fairchild Planar process provides total protection *The buffer element has a fan out of 25
with its integral oxide surface.

pul and wLogic are trademarks of Fairchild Semiconductor, a Division of Fairchild Camera and Instrument Corporation

10 CIRCLE 10 ON READER SERVICE CARD electronics

KLECTRONICS NEWSLETTER

Thermionic Solar Power System Passes Test

>

FEASIBILITY tests of a full-scale solar thermionic power system
indicate such systems have a potentional energy conversion effi-
ciency of 15 to 20 percent, General Electric reported last week.
Future system for space applications may produce 10 w/b.

However, efficiency obtained in
the initial test was low: 12.18 w
were produced, using 195 sq ft of
petal-shaped aluminum honeycomb
collectors and 105 vacuum thermi-
onic converters. Average converter
temperatures during the test were
about 250 C below the optimum of
1,150 C. GE says the converters are
capable of 1.5 watts at 2.65 percent
efficiency.

More efficient cesium vapor con-
verters have been developed and
advanced vapor types could be 25
percent efficient. One purpose of
the tests, performed under a $300,-
000 Air Force contract, is to indi-
cate design improvements.

The system includes switching to
apportion output between battery
and load during light and dark pe-
riods, a regulator to maintain out-
put at 26 to 29 v, a 23-cell nickel-
cadmium battery and solar orienta-
tion sensors. The latter adjust
pedestal through servo controls.

Nuclear Generator Runs
Buoy, Weather Stations

SNAP-7A NUCLEAR power generator
is being tested by AEC and Coast
Guard as a power source for ocean
navigation buoys. Similar gener-
ators are now being used at auto-
matic weather stations in the Arctic
and Antarctic.

The buoy power supply, made by
Martin Marietta, consists of stron-
tium-90 pellets whose radioactive
decay heat is converted to electric-
ity by 60 thermocouples. Output of
10 w at 5 v d-c is converted to 32 v
d-c to trickle charge nickel-cadmium
batteries. Life expectancy of the
power system is 10 years. Regular
buoy batteries must be recharged
every year or so.

Also this month, the Navy de-
livered to its base at McMurdo
Sound the Antarctic’s first nuclear

December 29, 1961

power plant. Martin prefabricated
the 1,500-Kw plant. Instrumenta-
tion was supplied by Tracerlab.

First of New Satellite
Tracking Stations Built

NASA REPORTS it is testing the key
station in its new network to track
and receive data from satellites.
The $5 million station, near Fair-
banks, Alaska, has an 85-foot dish
antenna and enough automatic
equipment to keep operating crews
small.

The program calls for a second
station at Rosman, N. C., and others
in the Far East, Newfoundland and
possibly elsewhere. The stations
will record data from orbiting as-
tronomical and geophysical observa-

Ben Franklin—1962

NEXT SUMMER, the bronze-hulled
school Azara will be sailing
around the Caribbean, trying to
get hit by lightning.

Originally outfitted as a gen-
erator of artificial atmospherics,
the Azara is used for research in
vif propagation and the poten-
tial uses of both natural and
man-made sferics for navigation
and long-range communications
(ELECTRONICS, p 53, July 22,
1960).

New program, directed by E.
A. Lewis, of Air Force Cam-
bridge Research Lab, will seek to
intercept lightning bolts, some
of which generate a terawatt of
power for about 100 usec. Bolts
will be triggered by shooting
wires into clouds with rockets.

tories. The first OGO, scheduled
for 1963, is to contain 19 experi-
ments.

NASA is building another 85-
footer near Fairbanks to receive
data from future Nimbus weather
satellites.

FCC May Give Community
Tv Grants a Back Seat

WASHINGTON—FCC has tentatively
decided that if a proposed com-
munity antenna tv service threatens
an existing tv station, the tv sta-
tion will be protected. The commis-
sion has directed its staff to write
a decision denying a microwave
grant to Carter Mountain Trans-
mission Corp., which is seeking per-
mission to provide service to three
Wyoming communities. If FCC
adopts the decision, it will report-
edly be the first time it has denied
such a grant to protect a going tv
station.

Pistol-Packaged Laser
Offered to Researchers

PORTABLE laser was commercially
introduced last week by Kollsman
Instrument for research and dem-
onstration applications in such
fields as optical communications,
crystallography and medicine.
The 9-in.-long ruby laser head is
packaged like a pistol with double
trigger grips. Power supply, oper-
ating from battery or line vower, is
in a case occupying less than a cubic
foot. Laser threshold pump power
is 90 joules, coherent light output
wavelength is 6,943 A and light
pulse train duration is 0.2 msec.

Looks Like West Ford
Package Is Space Junk

INTENSIVE RADAR search for Project
West Ford dipolés has yielded addi-
tional returns indicating that the
orbiting package has broken up into
several pieces. Several small ob-
jects in the right orbital plane ap-
pear at times close to the calculated
schedule.

The returns were picked up by
MIT Lincoln Laboratory’s Millstone

1

Hill radar, not the West Ford radar,
indicating the binder still hasn’t
released the dipoles. Chances are
the fragments will wind up as space
junk.

Neither Lincoln Lab nor Air
Force will say if there are plans
to try again. Unofficial sources
point out that the first launch was
made only after presidential ap-
’ proval and that a second try is not
likely until it is determined what
went wrong.

Airborne Computer Scans
Jet Engine Performance

COMPLEXITY of jet aircraft panels
is reduced by a digital computer-
scanning system announced last
week by Bendix. In the Air Force’s
four-engine test plane, 10 indicators
monitor 80 engine performance
conditions.

The system automatically calcu-
lates which engine is operating at
its most critical value for a flight
situation. This engine’s conditions
are displayed on vertical scales with
movable indices indicating maxi-
mum efficiency values.

If an engine function exceeds a
critical value, the crew is alerted to
the engine number. The crew can
check any engine at any time by
using selector switches.

Time Moves Faster,
NBS Changes Frequency

IRREGULAR rotational speed of the
earth—it’s getting faster—has
prompted National Bureau of
Standards and U. S. Naval Observa-
tory to change the standard fre-
quency and time broadcasts.

At zero hours GMT,. Jan. 1 (7
pm EST, Dec. 31), standard fre-
quencies transmitted by NBS sta-
tions (ELECTRONICS BUYERS GUIDE,
p R47, July 20) will be made higher
by two parts per billion.

Time pulses in 1962 will be off-

set from atomic time to correspond
with time based on earth rotation.
In 1962, frequencies will be 13
parts per billion lower than the
cesium atom clock, whose frequency
is 9.192631770 Gc. Changes will

12

also be made by Coast Guard’s east
coast Loran-C stations.

Microwave Tube Center
Is Slated for Midwest

CHICAGO—Hallicrafters and Com-
pagnie Generale de Telegraphie
sans Fil (CSF), of France, will set
up a firm to produce high-power
microwave tubes. The new com-
pany will be called Warnecke Elec-
tron Tubes, after the director of
CSF’s tube division. Ground for a
17,000 sq-ft plant will be broken
in February at one of three loca-
tions now under consideration in
the Chicago suburbs.

Robert F. Halligan, Hallicrafters
president, said at a meeting of com-
pany stockholders last week that it
will have complete facilities for
microwave tube R&D and produc-
tion. Hallicrafters, which is invest-
ing some $250,000, will have a 42
percent interest, CSF the rest.
Maurice Ponte, of CSF, will be
chairman of the new firm.

Seattle Schools Plan
F-M Emergency System

SEATTLE—School board plans to in-
stall an f-m emergency signal radio
system in 119 school buildings.
The installation, subject to FCC ap-
proval, is primarily a civil defense
safety measure, but will also give
the schools what amounts to a
closed-circuit communications sys-
tem. Additional expense will be
$28,800 for receivers plus $60 for
each installation.

Four Subcontractors
Named for Apollo

NORTH AMERICAN AVIATION last
week named four subcontractors for
the command module of NASA
Apollo spacecraft. Collins Radio will
receive more than $40 million for
telecommunications; Minneapolis-
Honeywell Regulator, $30 million,
stabilization and controls; AirRe-
search, $10 million, environmental
control, and Radioplane, $1 million,
recovery system.

in ‘Breee:.... 5

MAGNETIC Recording Industry As-
sociation members expect sales
gains of 12 to 15 percent in f-m
stereo and 20 to 50 percent in
tape. Tenney Engineering esti-
mates environmental test and
equipment volume in 1961 was
$225 million, up $75 million.

SIMULTANEOUS control of as many
as 20 satellites will be studied by
Planning Research Corp. under
Lockheed contract.

BURROUGHS is setting up its own
finance corporation to expedite
computer sales and leasing.

TRAINING simulator contracts in-
clude $2.2 million to Curtiss
Wright and $668,000 to Link,
from Navy. Link will also build
four fighter pilot trainers for
Japan, which is getting 200
F104J’s.

GROUND DATA handling subsystem
of the AN/USD-7 Air Force re-
connaissance system will be made
by Airborne Instruments Lab
under $4 million contract. The
$40 million system is being de-
signed and produced by AIL,
General Telephone, Sperry Rand,
Raytheon and Filtron.

OTHER AIR FORCE awards include
$7.5 million to Adler Electronics
for long range, transportable
communications systems; $2 mil-
lion to AC Spark Plug for stellar
inertial guidance R&D; $1.6 mil-
lion to CompuDyne for analog-
digital engine test stands; $1.8
million to Raytheon for radar
countermeasures.

NAVAL equipment contracts include
$300,000 to Transonic for sono-
buoy transducers; $195,000 to
Packard Bell for a digital svs-
tem; $140,000 to Nytronics for
airborne decoders.

ARMY orders include $922,000 to
Taffet Electronics for field com-
munications components; $250,-
000 to Craig Systems for com-
munications shelters; $105,000 to
Datex Corp. for an automatic
meteorological data acquisition
system.

MOTOROLA will build a 500-mile
microwave relay for Santa Fe
Railway; Philco, a 250-mile net
from Voice of America studios
in Washington to the 4.8-Mw
transmitter at Greenville, N. C.

electronics

Model 187B-SL

COMPLETE LIN
OF VERSATILE,

Model 187B-XB
13%”

for SL, S, C, XB and X Frequency Bands x grea i)

Model 187B-X ”

Five models covering five bands These Sierra high-power waveguide terminations are extremely

useful as dummy loads in calorimetric power-measuring systems.
They feature rugged construction, with rigid plastic water tube
mounted in waveguide section, diagonally oriented for impedance
matching. Chokes and shielding minimize rf leakage, and a
heater element built into each model permits rapid, accurate
calibration of a calorimetric power-measurement system

against a low-frequency standard,

Three models useful iri pressurized systems
VSWR less than 1.10

High average, peak power ratings

Low rf radiation

Calibration heaters in all models

Model Number:

Frequency Range:
VSWR:

Power Average:

Peak Power: (Unpressurized)
Max. Air Pressure:
Waveguide:

Connector:

Recommended Water Flow:
Pressure Drop at Rated Flow:
Max. Water Pressure:

Water Temperature:

Water Capacity:

Water Renewal at Rated Flow:
Heater Resistance:

Heater Rating:

Length:

Price:
*Not pressurized

187B-SL

1.7 to 2.6 kme
< 1.10 to 2.4 kmc
< 1.15 to 2.6 kme

20 kw

2 megawatts
*
RG-105/U
UG-437A/U
2 gpm for 10 kw
10 psi
80 psig
0 to 70°C
18.5 cu. in.
Once per 2.5 sec,
4.5 ohms
10 kw at 2 gpm
50 in.
$600.00

1878-S

2.6 to 4.0 kmc
less than 1.10

10 kw
1 megawatt

RG-75/U
UG-584/U
2 gpm for 10 kw
10 psi
80 psig
0 to 70°C
3.5 cu. in.
2 times per sec,
9 ohms
5 kw atl gpm
32 in.
$500.00

Data and prices subject to change without notice. Prices f.0.b. factory

187B-C

§.8 to 8.2 kmc
less than 1.10

5 kw

500 kw
45 psig
RG-50/U
UG-344/U
1 gpm for 5 kw
10 psi
80 psig
0 to 70° C
0.85 cu. in.

4.3 times per sec.

14 ohms
3 kw at 1 gpm
20 in.
$425.00

187B-XB

7.0 to 10.0 kmc
less than 1.10

3 kw

250 kw
45 psig
RG-51/U
UG-51/U
0.6 gpm for 3 kw
10 psi
80 psig
0 to 70° C
0.42 cu. in.

5.3 times per sec,

20 ohms

1 kw at 0.6 gpm
17.25 in.
$400.00

187B-X

8.2 to 12.4 kmc
jess than 1.10

2kw

150 kw
45 psig
RG-52/U
UG-39/U
0.4 gpm for 2 kw
10 psi
80 psig
Oto 70°C
0.20 cu. in.
7.4 times per sec.
20 ohms
1 kw at 0.4 gpm
13.5 in.
$375.00

For complete details, see your Sierra Representative or write direct.

Sierra also offers its Model 186 Series Coaxial Water Loads, covering dc to 4 kme.

SI@rra SIERRA ELECTRONIC CORPORATION

A Division of Philco Corporation
6807A BOHANNON DRIVE . DAvenport 6-2060 . MENLO PARK, CALIFORNIA, U.S.A,
Sales representatives in all principal areas
Canada: Atlas Instrument Corporation, Ltd., Montreal, Ottawa, Toronto, Vancouver
Export: Frazar & Hansen, Ltd., San Francisco 6807

December 29, 1961 CIRCLE 13 ON READER SERVICE CARD 13

COAXIAL
ca BL E-S

-».-FOAMED
DIELECTRIC

Raychem Corporation's irradiated
modified cellular polyolefin miniature
coaxial cables fill a specific industry
need. Small high temperature cables
manufactured with conventional dielec-
tric materials have solved many prob-
lems of space and weight, but not
without sacrificing certain important
mechanical properties.

A series of cables utilizing high
strength, solderable, irradiated cellu-
lar polyolefins have been created. For
a specific impedance they are dimen-
sionally equivalent to standard poly-
tetraflouroethylene dielectric miniature
RG series cables.

The unique foam, with its low dielec-
tric constant of 1.5, permits a radical
increase in center conductor size. This
results in elimination of the widespread
problem of center conductor breakage
while significantly lowering both ca-
pacitance and attenuation. Coincident
weight reductions of up to 50% are
also achieved.

leader in radiation chemistry

®

RAYCHEM

CORPORATION

OCAKSIOE AT NORTHSIOE
REOWOOD CITY. CALIFORNIA

CIRCLE 14 ON READER SERVICE CARD

WASHINGTON OUTLOOK

MINUTEMAN PRODUCTION will be in-
creased as a result of the Pentagon’s deci-
sion to scrap the mobile version and concen-
trate on fixed-base deployment. Funds
initially earmarked for the mobile system
will now be spent on additional underground
launching silos. Concern over guidance was
a factor in the decision, but the overriding
reason was cost. The railcar version costs
close to 50 percent more than the fixed-base
missile.

NAVY will use its own advanced fire control
system in the carrier-based version of the
TFX tactical fighter plane which it and Air
Force are developing jointly. Navy’s fire
control system will presumably be optimized
for air-to-air operations, as distinguished
from the Air Force’s emphasis on air-to-
ground combat. Navy’s Bureau of Weapons
plans to award an R&D contract shortly
for the new system.

Similarly, Air Force plans to award the
prime contract on TFX within the next
couple of months. TFX is planned as a suc-
cessor to the Air Force’s Republic F-105
and the Navy’s McDonnell F4H. Initial
operation is scheduled for about 1966. Mean-
while, the Air Force plans to buy F4H air-
craft next year and reduce scheduled pro-
duction of the older F-105.

UPCOMING CONSOLIDATION of military supply management
of electronic parts will cover 450,000 different common-use Penta-
gon catalog items, including a considerable quantity of electrical
components. The items represent a military inventory worth
$600 million with annual purchases now averaging $150 million.
No decision has been reached on when the consolidation will be
made.

CENSUS BUREAU has started issuing its detailed statistics
from the 1960 census on the use of appliances, tv and radio sets
in U.S. homes. Brief advance summaries have been issued for
a number of states. Both advance reports, and the vastly more
detailed final reports, have been issued for Utah and Vermont.
The rest can be obtained as they are issued, between now and
May 1, from the Bureau.

Validity of comparisons between the 1960 and 1950 census
figures has been questioned because of changes in reporting
methods. For example, in 1950 census takers asked the questions,
but last year, those selected for detailed queries filled out the
forms themselves. In addition, the definition of “household”
was broadened in 1960. In some cases, the number of homes
having a particular appliance increased, but the saturation per-
centage declined.

electronics

FOR THE MISSILE

December 29, 1961

RAYCHEM
WIRE AND

COAXIAL .

CABLES

AND SPACE AGE

CORPORATION

4 RAYCHEM
®

CIRCLE 15 ON READER SERVICE CARD

15

| % | |
a a .

AND PRECISION FORK
1 TO 40,000 CYCLES

i : | i ll

TYPE 2007-6 FREQUENCY STANDARD

Transistorized, Silicon type
Size, 1%" dia., x 342” H., Wt., 7 oz.
Frequencies: 360 to 1000 cy.
Accuracies:
2007-6 + 0.2% (—50° to +85°C)

This frequency standard (360 R2007-6 + .002% (+15° to +35°C)

W2007-6 + .005% (—65° to +85°C)
Input: 10 to 30V DC at 6 ma.
Output: Multitap, 75 to 100,000 ohms

TYPE 10

145° x! en

or 400 cycles) is accurate to
+ 50 parts per million at 10° to
35°C. Aging has been greatly
minimized.
TYPE 2001-2 FREQUENCY STANDARD
Size, 334” x 442" x 6” H., Wt., 26 oz.
Frequencies: 200 to 3000 cycles
Accuracy: +.001% at +20° to +30°C
Output: 5V at 250,000 ohms
TYPE 2007-6 P ,
Input: Heater voltage, 6.3 - 12 - 28
B voltage, 100 to 300 V, at 5 to 10 ma.
TYPE 25 > :
Accessory Modular units are available to
TYPE 2001-2 divide, multiply, amplify and power this
- unit.

External power of 1.4 volts at 6
mitroamperes powers the unit.

TYPE K-5A FREQUENCY STANDARD

Size, 342” x 3” x 1%"

Weight, 11 lbs.

Frequency: 400 cycles

Accuracy: .03%, —55° to +71°C

Input: 28V DC +10%

Output: 400 cy. approx. sq. wave

at 115V into 4000 ohm load (approx. 4W)

TYPE 25 PRECISION FORK

Size, 56” dia. x 2%"

Weight: 2 ounces

INQUIRIES INVITED Frequencies: 200 to 1000 cy.

Accuracies:

For over 20 years we have made fre- R-25T and R-25V + .002% (15° to 35°C)
quency standards and precision tork 25T and 25V + .02% (—65° to 85°C)

units for applications where consistent For use with tubes or transistors
accuracy and rugged dependability are ;

vital. Shown ore just a few typical
examples.

Some users integrate our products with

instruments of their own manufacture. In

other cases we develop complete assem- & M E R I C a N T I M E P R O D U C T S
blies to meet special needs. DIV. OF BULOVA WATCH COMPANY, INC.

You are invited to submit any problems 61-20 Woodside Ave., Woodside 77, L. I., N.Y

within the area of our activity for study

by our engineering staff. WESTERN OFFICE, 234 N. LAKE AVE., PASADENA. CALIF

16 CIRCLE 16 ON READER SERVICE CARD

electronics

ESSING THE
BEAM

WHAT IS E-BEAM EQUIPMENT?
WHAT IT IS: Alloyd Electronics’ WHAT DOES IT DO? CAN IT BE PUT TO possible contamination free,

electron beam equipment con-
sists of a line of completely self-
contained units employing elect-
ron bombardment heating, carried out in a vacuum,
for evaporating, welding, brazing or zone refining.

MAJOR APPLICATIONS:
Evaporation: Alloyd electron beam equipment can be
used to produce high purity thin metallic and non-
metallic films by vapor deposition of high temperature
materials. Films can be made from the most difficult ma-
terials, including beryllium, tantalum, silica, alumina.
Useful thin-film applications: Electronics, where thin
films can perform as capacitors, resistors, magnetic
memory devices, etc. . . . optics, where thin films with
unusual optical properties are being developed .
countless other applications.

..and

WORK FOR YOU ECONOMICALLY?

narrow heat affected zone welds
in titanium, beryllium, tungsten,
molybdenum, etc.

MAJOR ADVANTAGES OF ALLOYD EQUIPMENT:
1. Modular design, for flexibility: basic components of
any Alloyd system, including electron gun and power
supply, vacuum chamber, and vacuum pumping system
are available in practically unlimited combinations for
maximum flexibility, and can be easily and economically
tailored to any application. 2. Voltage is low and safe
(30,000 volts max.) eliminating x-ray hazards to the op-
erator. 3. Maintenance is simplified. For example, the
electron gun filament in any Alloyd unit can be serviced
without removing the gun. 4. Operation is simplified.
Fingertip controls, located directly underneath the cham-
ber, make for maximum operating ease and efficiency.

Benefits to be derived from Alloyd’s look-ahead modu-
lar design are both numerous and substantial, not only in
terms of reliability, but in terms of flexibility and cost.

It will be well worth your while to write today for com-
plete information.

Welding: Alloyd Electron Beam Welders (see below) are
designed for experimental or production welding and
brazing of refractory and reactive metals. High vac-
uum is coupled with high power density — makes

alloyd electronics corporation WF 35 Cambridge Parkway, Cambridge 42, Massachusetts

4 Mark Vi Electron Beam Welder — for clean, crack-free welds in
even the most refractory and reactive metals by electron bombard-
ment. High vacuum eliminates contamination. Ultra-narrow heating
zone permits optimum control and precision in handling very thin
pieces or welding thin-to-thick sections.

Mark V Electron Beam Evaporator— a reasonably priced, highly
flexible unit for producing thin metallic and non-metallic films by
vapor deposition through electron bombardment heating. Completely
self-contained. An invaluable research and development tool for thin-
film applications, including micro-miniaturized electronic circuitry,
optical filters, resistors, capacitors, memory devices, countless
other components.

The Electron Beam at your service — Our laboratory is part of an
advanced, complete facility for electron beam welding, brazing,
evaporating, melting and zone refining maintained by Alloyd to meet
custom requirements. We also offer engineering, consulting and R&D
services in systems design and development. Ask us for complete
information.

5 l=Y=)
EYE

CIRCLE 17 ON READER SERVICE CARD CIRCLE 18 ON READER SERVICE CARD->

Almost all security minded nations depend on

ePEARY

4 HS Som de), Iie
TUBE
DIVISION

systems using Sperry electronic tubes

SPERRY RAND CORPORATION
GAINESVILLE, FLA.
GREAT NECK, N. Y.

With Wrap” tools

these hands wrap up wiring jobs fast

Keep expensive hands working at top efficiency and ingly secure, conquer vibration failure and corrosion.
get permanent, solderless electrical connections in a And only Gardner-Denver offers a complete line of
hurry with Gardner-Denver “‘Wire-Wrap”’ tools. equipment for making such connections— including

Proved superior by leaders in communications and custom-designed, automatic machines to expedite
electronics, solderless wrapped connections are last- multiple operations.

Air-powered Electric-powered Manual wrapping and Hand-Squeeze
“Wire-Wrap” tool. “Wire-Wrap” tool. unwrapping tools. “Wire-Wrap” tool.

EQUIPMENT TODAY FOR THE CHALLENGE OF TOMORROW

GARDNER - DENVER

Gardner-Denver Company, Quincy, IIlinois—Offices in principal U.S., Canadian and Mexican cities
in Canada: Gardner-Denver Company (Canaca), Ltd., 14 Curity Ave., Toronto 16, Ontario
international: Gardner-Denver International Division, 233 Broadway, New York 7, N. Y

Internationa! Offices: Buenos Aires. Argentina; Artarmor, N.S W. Australia: Brussels, Beirium. Rio de Janeiro, Brazi
Santiago, Chile: Barranquilla, Colombia; Lima, Peru; Ndola, N. Rhodesia, Salsbury, S. Rhodesia, Johannesburg Transvaa

20 CIRCLE 20 ON READER SERVICE CARD electronics

1
Microsecond

Now available from Daystrom as standard units, these 1 »sec
modularized core memories permit manufacturers of digital
machines to eliminate expensive component development.
The modules offer design flexibility never before available
to computer engineers. Full read-write cycle time for the
modules is 1 psec or less, and access time is typically 0.5
psec. The standard memory has a capacity of 1024 words,
50 bits to the word, and can be expanded in multiples of this
capacity up to 4096 words and 200 bits per word. Components
are stacked to give high package density. Only two different
voltages ...+20V and —20V... are required, and the full driv-
ing current is only 360ma. All solid-state and highly reliable, the
standardized modules reflect Daystrom Military Electronics Di-
vision’s extensive experience with MIL memories and circuitry
such as the NORC and 465L systems. Send for technical data.

| DaAYstRom , INCORPORATED
Lv

MILITARY ELECTRONICS DIVISION

ARCHBALD, PENNSYLVANIA «+ JERMYN 876-1500

December 29, 1961 CIRCLE 21 ON READER SERVICE CARD 21

#

7

An unusual combination of advantages found only
in mercury-wetted relays has led many design engi-
neers to specify them for tough switching jobs. Here
are but 3 typical characteristics of our JM series:

RELIABILITY. Sealed-in-glass mercury contacts are
renewed with every operation. Won't pit or weld.
Make or break is positive . . .every time. No bounce,
no chatter. Signals ranging from a few micro amps
to 5 amps are switched with singular consistency.

LONG LIFE. Think in terms of billions of operations
when considering JM series relays. Proper applica-
tion, of course, is a requisite.

SPEED. Operate time is just less than 3 milliseconds
using 2 watts of power. Release time is about 3.2
milliseconds. Thus, relays can be driven 100 times
per second.

If your project calls for exceptional relay perform-
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P&B STANDARD RELAYS ARE AVAILABLE AT YOUR LOCAL ELECTRONIC PARTS DISTRIBUTOR

POTTER & BRUMFIELD

PRINCETON, INDIANA

POTTER & BRUMFIELD, DIVISION OF AMF CANADA LIMITED, GUELPH, ONTARIO

PSI ... Lhe industry’s Number One supplier

of Silicon Welded Assemblies now announces

MICRO LOGIC
MODULES

Circuits at prices as small as their size

Dual Emitter Follower Dual Inverter

|Flip Flop [eal

Psi9i3 4

“And” Gate “Or” Gate

all operating at two megacycles

Here is the logical answer to the logic circuit designer
seeking micro-size units for the microminiaturization
program he needs to put into effect now!

Delivery is good ... prices are surprisingly low...
performance and reliability are tops! These new 2mc
Micro Logic Modules will measure up to your most
exacting standards of reliability because PSI Micro-
Diodes and Micro-Transistors are used in every unit.

All-welded assembly and epoxy encapsulation assures
high resistance to shock and vibration . . . excellent
moisture integrity. The Micro Follower, Inverter and
Flip Flop are %” cubes; the gates only 7/16”. Terminals
are on .1” grid spacing.

For detailed specifications, prices and delivery sched-
ules call any PSI Field Engineering office. See your
Yellow Pages.

A Pacific Semiconductors, Inc

AN A SUBSIDIARY OF THOMPSON RAMO WOOLDRIDGE INC.

12955 Chadron Ave., Hawthorne, California e« Cable: PSISOCAL TWX: HAW CAL 4270 OR 8-4711, OS 9-2281

~<—CIRCLE 22 ON READER SERVICE CARD

CIRCLE 23 ON READER SERVICE CARD 23

+
'

[
|

(Actual Size)

Alternate Action
Lighted Pushbutton

In one cubic inch: double-pole double-
throw switching; split-color screen
(your choice of 15 color combinations);
two lamps under screen. Also available
in same size: momentary action switch,
and indicator unit without switching
function. Write for Data Sheet 182:

MICRO SWITCH ... FREEPORT, ILLINOIS
A division of Honeywell
In Canada: Honeywell Controls, Limited, Toronto 17, Ontario

Honeywell
MICRO SWITCH Precision Switches

electronics

nae

MICRO SWITCH

HAS MORE ANSWERS
FOR CUSTOMIZING

YOUR CONTROL PANELS!

‘i i
Modular earicts

795 Rocker “6 AT" “13 AT” toggle “17 AS” rotary “2 PB” push-button
“Series 2”

actuator switch t | itch ith indi lecto itch itch a mobi
“50 PB” lighted ctu r swi oggie switc with tabindicator select r swite switch assembly
push-button assembly

MORE SWITCH DESIGNS, MORE FLEXIBILITY IN THE MICRO SWITCH PUSH-BUTTON LINES

When you want a control panel precisely tailored
to your equipment and absolutely reliable, start
with MICRO SWITCH. You'll find the wider selec-
tion fits your ideas, rather than your ideas having
to fit the selection.

New “302 PB” Miniaturized Lighted Push-
Button Switches provide infinite lamp life,
double-pole double-throw switching and 2-color
indication in a unit requiring only one cubic inch
of panel space.

Modular “Series 2” Lighted Push-Button
Switches offer customized combinations of eight

different basic switches and dozens of colored
indicators—and they snap together without tools.
New truncated display screens add dimensional
visibility.

MICRO SWITCH also makes the “Series 50 PB”
lighted push-button switches as well as hundreds
of different toggle switches and assemblies.
Everything you need for customizing control pan-
els. See the Yellow Pages for the nearby MICRO
SWITCH Branch Office. Write for illustrated cata-
logs on push-button and toggle switches for con-
trol panels and machine control stations.

December 29, 1961 CIRCLE 25 ON READER SERVICE CARD 25

MICROWAVE RADIOMETER

The measurement of this noise radiated by all objects according
to their temperature and surface characteristics makes possible:

Detection of distant invisible radio stars
tric Amplifier with regulated Location of icebergs through clouds from high flying aircraft

pply developed for use in

D me range Mapping of the surface of the sun

All-weather celestial navigation

Detection of objects under the ground or snow
Mapping of the earth’s surface from moving aircraft

MELABS has been a pioneering leader in this relatively new
field. Its activities have ranged from theoretical studies to
development and manufacture of a wide range of radiometer
systems and components.

SYSTEMS: RMR-1 35 Gc Radiometer System (illustrated to the left Ferrite SPDT Switches—electronically switched at 100-1000 cps for
above) features 0.5°K sensitivity and 0.8° antenna resolution. Uses switching between antennas and reference loads. Available from
1 ke ferrite reference switch. Reference is adjustable from 77 K 1 to 35 Gk

to 15,000°K

TWT Radiometers at 1400 and 3000 mc feature low noise TWT broad-
band amplifiers

Solar Spectroheliograph—3000 mc radiometer for mapping TWT Preamplifiers—for broadband radiometers with noise figures of
sun's surface. 5-10 db. Mounts on antenna

Ferrite Circulators and Isolators with ultra-low loss, (0.1 db typical
for radiometer front ends

COMPONENTS: Parametric Preamplifiers—availabie from 700 mc to Masers—broadband traveling wave types for the ultimate in
6000 mc with broad bandwidths (20% or greater system sensitivity

Melabs invites your inquiries on Radiometer Systems and Components.

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Employment opportunities at Melabs are exceptional for ambitious engineers and physicists; write in confidence,

DEPT. B-7 AN EQUAL OPPORT

26 CIRCLE 26 ON READER SERVICE CARD

electronics

A basic formula from Information Theory ... provides a measure of the amount of information in a particular type of message, such as TV ... helps determine the frequency
bandwidth, for example, required to transmit the messages. Information Theory, pioneered at Bell Laboratories, guides the search for better communications systems

DISCOVERY

AT BELL TELEPHONE LABORATORIES

New knowledge comes in many forms. Sometimes it comes in
a mathematical formula. Usually it comes after much thought
and experiment and the fruitful interaction of different minds
and abilities. Most often, too, a particular discovery is small.
But many small discoveries have a way of leading to big ad-
vances at Bell Laboratories—advances like the transistor .. .
or, more recently, the gaseous optical maser, forerunner of
communications at optical frequencies. Opportunities for dis-
covery are enhanced by the abilities of the scientists

and engineers and the range of the facilities at Bell

Laboratories, world center of communications re-

search and development.

Iterative Techniques Widen Applications ot

Small analog and digital computers at Eastern Joint Computer Conference

point up data processing trends. Input-output systems gain in speed

1

By WILLIAM E. BUSHOR,

Senior Associate Editor

WASHINGTON—-Iterative techniques
—-opening the door to application of
analog systems in statistical work—
was one of the important trends evi-
dent on the exhibit floor at the
Eastern Joint Computer Confer-
ence. While big computers were
prominently showcased, it was the
smaller computers—both analog
and digital—which set the pace.

Shown was GPS _ Instruments’
iterative analog computer for simu-
lating missile flight paths. High-
speed predictions of impact point
location can be determined from
given missile data.

The computer, operating in a
fast, repetitive mode, accepts flight
data as its initial conditions. It com-
putes the flight paths, evaluates
how far the missile will miss the
target and makes_ incremental
changes in flight path parameters to
minimize miss distance.

The new parameter values are fed
back to the missile control system to
correct the trajectory. New flight
data is then used for another itera-
tive solution series. In the photo, an
engineer varies the controls to
simulate changing flight data. Ef-
fect on missile trajectory prediction
is displayed by the cro and an x-y
plotter.

The system gives 50 solutions a
second. Because a time scale com-
pression of 3,000 to 1 is used, wide-
band components such as a d-c to
1-Mc operational amplifier and d-c
to 40-Ke multiplier are needed.

GPS expects this approach can
also be used to simulate sampled
data systems and transport delays,
and to evaluate double integrations
using multiple time scale _ inte-
grators.

Another new analog computer is

28

Electronic Associates’ solid-state
Pace TR-48. This desk-size unit has
enough capacity for complex re-
search and engineering problems,
particularly in the aerospace and
process sciences, but does not need
an air conditioned environment or
special power supply. It can be
placed on a cart and wheeled around
labs or engineering areas.

While parts of the computer are
operating at high repetitive speeds,
the remaining circuits can work on
other problem variables at slower
repetitive rates or real time. Thus,
it can handle certain classes of de-
sign problems—such as multidi-
mensional flow and heat transfer—
ordinarily solved on larger com-
puters, EIA says.

Among other small computers
were Comcor’s analog system, Har-

EJCC SIDELIGHTS

Change was the byword for this,
the 19th Joint Computer Confer-
It had a new sponsor, the
American Federation of Informa-
tion Processing Societies. IFIPS
does not plan to continue the re-
gional format next year.

Attendance, more than 4,000 con-
ferees and over 90 exhibits, was the
largest yet. There were 29 papers
—selected from a total of
after 961
and 27 movies presented.

The theme was “Computers: Key
to Total Systems Control.” The
keynote speaker was D. L. Bibby,
president of Remington Rand. He
urged that the ratio of time spent
in hardware’ development as
against improving computer utili-
zation, 1,000:1, be
changed.

Computers, he feels, are not ex-
ploited sufficiently for
benefit to
ness, manufacturing
medicine,

ence.

242

manuscripts reviews—

now about

maximum
national defense, busi-
techniques,
sciences and education.

vey-Wells Electronics’ general-pur-
pose digital system and Control
Data’s 160-A. The latter, a desk-
sized digital computer, exchanges
data with input-output devices at
any rate up to 70,000 words a sec-
ond. It buffers data while comput-
ing or while the operator manually
enters data.

Continuing problems of develop-
ing peripheral equipment able to
match computer speeds aroused the
usual interest in input-output de-
vices. This year, the emphasis cen-
tered on recording equipment.

For example, General Dynamics/
Electronics’ S-C 4020 can operate
on-line at most computer speeds or
can work off-line from magnetic
tape. It records characters at 21,000
a second and plots graphs at 12,500
points a second. Complex multiview
engineering drawings, schematics,
numerical tool paths or diagrams
like the Pert network illustrated
(ELECTRONICS, p 30, Nov. 17) can
be made in a half second. Curves,
tables, alphanumeric printing or a
combination of these, derived from
digitally-coded data, are displayed
on a shaped beam tube. The image
is split optically to fall on the lenses
of microfilm and _ photorecording
cameras, producing both films for
storage and hard copy on paper.

A special projector allows conven-
tional formats to be combined with
the image, making preprinted
forms unnecessary. An axis gener-
ator draws horizontal and vertical
graph axes starting at any point in
the display area. A vector gener-
ator draws straight lines between
any two points.

Omnitronics’ Omni-Data ETR-7
gets around mechanical tape punch-
ing by electrostatically producing
black spots on tape in the same
code configurations used on punched
tape. The company says this meth-

electronics

Analog Systems

GPS analog system plots
changing missile trajectory

od is reliable, long-lived and can be

used with high-speed digital com-

puters.
Demonstrated with Omnitronics’

photoelectric tape reader, the sys-

tem recorded 400 characters a sec-

ond. Higher speeds and greater

packing densities are possible, it

was reported. FLIGHT
Ampex introduced a random-ac- _ !NITIAL SILE PATH

Ae ape CONDITIONS sige AND

cess ferrite core memory which op- —(veLocity, \

erates at 1.5 usec for each complete Ho Saas OMPUTATION a

operating cycle (667 Kc). Each DATA

module of 32 planes can store 2,048

56-bit words. The module uses a

linear (word select) drive system f

and operates in the read-restore, System uses

. . : automatic

clear-write and split read-and-write praeeereatae

ee MISSILE PARAME TERS COMPUTA logic control
Basic unit of the TM-4 tape mem- — CONTROL TIONAL

ory is a plastic strip with 30-mil- SYSTEM

thick ferrite cores mounted along

the edge. A read and write drive

line traverses all cores associated

with one word. Planes contain 35

strips. Sense-digit lines are

threaded through each core in a

plane associated with a specific dig-

ital position in a word.
For preventive maintenance of

tape, General Kinetics showed a

cleaner which removes loose oxide,

tape base chips and dirt without af-

fecting stored data. It uses high-

energy sonic and ultrasonic cavita-

tion in a detergent solution directed

at tape edges and surface. Operator of EAI computer can use oscilloscope for readout of repetitive
Other systems, previously an- operation

nounced but exhibited for the first

time, included Digitronics’ system

for transmitting tape or card in- :

put information over phone lines to Turns |

a central computer at 1,500 wpm. . ANN | 1% } AY
National Cash Register operated \ , | A}
their memory which uses cards car- : : i

rying seven magnetic tracks. The

memory has 16 cartridges, each con-

taining 256 cards, each of which

can store 21,700 characters. Any

ay a Pert network is formed on image tube of GD/E recorder (left). Basic
card can be selected in 170 msec.

unit of Ampex memory is string of cores on plastic strip

December 29, 1961

ate
ae

orbeamienclt

ant atelectasis Patt aEe
ei

gamete

Pilot’s reactions to flight problems
are shown on control console

Safety engineer sits at monitor
console as gondola moves inside
ball-shaped plastic “universe”

Gondola Makes Dry Runs in Space

DALLAS—Space flight simulator
controlled by an analog-digital com-
puter system is being used by Ling-
Temco-Vought to duplicate realis-
tically flights in manned orbiting,
lunar and interplanetary vehicles.
All phases of a mission, including
launch, orbit, rendezvous, mid-
course guidance, reentry and land-
ing, can be performed. To heighten
realism, a tv system shows the pilot
the type of space scenes he would

see through a periscope. The pilot _

is also watched, on a tv monitor.

The pilot sits in a single-place
gondola with a complete set of
working controls and instruments.
Movement of the gondola, instru-
ment operation and a star field are
controlled by the computers as the
pilot is subjected to flight : situa-
tions. The company plans to add
noise and other factors contribut-
ing to pilot sensations and instru-
mentation to measure his physical
reaction to flight stresses.

A general purpose analog com-
puter with added analog-digital
conversion and digital computation
capabilities is used. The system in-
cludes 800 operational amplifiers
and potentiometers, 11 multipliers,
47 multiplying servos, 31 function
generators, 13 six-channel record-
ers and six course plotters. All the
cockpit instruments are repeated on
the control panel.

The flight simulator is part of a
simulator center under develop-

30

ment. An automatic controls evalu-
ation simulator is also in operation
and an environment simulator for
testing satellites, vehicles and sys-
tems will be added soon.

The company recently installed a
nuclear facility with a 3-Mev Van

de Graaf accelerator and a plasma
arc machine. It is being used to in-
vestigate radiation effects on mate-
rials and equipment, to design
plasma engines, to study the nu-
clear-powered missile, Slam, and for
other development work.

Engineer Supply Drops Sharply

SHORTAGE of engineering graduates
during the next several years is pre-
dicted by the Engineering Man-
power Commission of Engineers
Joint Council, New York. The short-
age will come at a time when de-
mand is rising sharply, EMC said,
indicating a “crisis” may be near.

A survey of 186 colleges showed
that freshmen engineering enroll-
ments have dropped two to three
percent this vear, continuing the
trend for the fourth vear. Only the
East South Central, Mountain and
Pacific states showed an increase.
Middle Atlantic enrollments
dropped the most, 6.6 percent.

Engineering students represented
10.8 percent of all freshmen in
1957. This year, they are less than
seven percent. In 1950 there were
52,700 graduating engineers; in
1960, 37,800. Present enrollment
will yield about 32,000 in 1965.

EMC points out that this will not

supply half the average annual de-
mand forecast by the National
Science Foundation: 81,000 engi-
neers a year during 1961-70.

Some of the drop may be reflected
in increased science enrollments.
Among 46 schools that supplied in-
formation on both types of enroll-
ments, science enrollments rose 24.4
percent, but engineering enroll-
ments also rose 2.5 percent in these
schools.

Computer Runs
Parking Garage

NEW YORK—A fully automatic ele-
vator garage opened here this
month. One attendant-cashier sit-
ting at a console selects a parking
stall for a customer and collects the
fee. The rest of the operation—

electronics

from parking and retrieving the
car to computing the fee—is han-
dled by a small computer and other
controls.

Developed by Speed Park, Inc.,
and Otis Elevator Co., the garage
on West 43rd St. has two elevator
towers, each servicing two parallel
sections nine stalls long and eight
stalls high. Some 27 cars can be
parked in 10 minutes.

The motorist drives his car onto
one of two parking stations and
leaves it. A barrier is raised around
the car. The attendant selects a key
numbered and cut to designate the
stall. The key is inserted in a key-
hole. Photoelectric cells sense the
stall location from the key shape.
The key is given the motorist as his
claim check, along with a printed
record of stall number and time.

The car is lifted in the station on
parallel ribs. Steel fingers on an ele-
vator draw the car into the ele-
vator. The elevator delivers the car
to the stall. The operation is re-
versed when the motorist returns
with the key. The parking fee is
displayed on a screen and time and
fee are printed on a receipt.

The parking computer is based
on standard digital logic modules
made by Digitronics Corp. It has a
magnetic memory of some 8,100
cores, 30 for each stall. They store
information on whether a stall is
occupied, parking time and date.

Key inserted in control board
selects parking stall

Car is lifted from parking station
by fingers of elevator

CIRCLE 31 ON READER SERVICE CARD—>

PS-207 7-channel recorder used in Trieste bathyscaph

THINK DEEP

You're looking at the natural habitat of the Pl tape recorder. Beneath the surface, you'll
find Pl tape machines at work in conventional and nuclear submarines, in exploration of
the ocean floor, in ASW sounding and detection buoys, and in oceanographic research.
You'll find them wherever there’s an exceptional premium on reliability — cruising under
the polar ice cap, probing the darkest depths aboard the Trieste bathyscaph, handling
important Polaris telemetry and computer assignments.

You needn't go very deep to discover why Pl recorders need very little of man’s most
valuable undersea commodity — space. They pack far more performance into far less space
than conventional recorders, require less power, generate less heat, need less mainte-
nance. Their rugged, light-weight, all-solid-state design offers simpler installation, easier
mobility.

Pl recorders aren't all beneath the surface. They're veterans of orbital satellite flight, and
are familiar equipment in hundreds of laboratory, scientific, and industrial applications.
They’re made in numerous configurations, for analog or digital recording on 1 to 16 or
more tracks, in standard speed ranges push-button controlled from 15/16 to 60 ips, with
frequency response from 0 to over 200 kc.

Whether your recording applications are under the sea or above it, we'd like to demon-
strate Pl’s approach-in-depth. And whether you are presently using strip charts, punched
tape, or pad and pencil to gather data, you may find that upgrading to magnetic tape not
only provides increased flexibility and reliability, it may also more than pay for itself
through savings in time and money. Ask your PI representative for our current brochure,
or write direct.

1011 Commercial Street * San Carlos «+ California
Phone LyYtell 11-4441 .
Representatives in principal cities throughout the world

TWX: SCAR BEL 3O

(J) PRECISION INSTRUMENT COMPANY

Pl invites inquiries from design, application, and sales engineers.

Ar.

"MODEL 500
"INTERFERENCE LOCATOR

a me tm te hr

This versatile instrument is a
highly sensitive interference lo-
cator—with the widest frequency
range of any standard available
unit! Model 500 tunes across the
entire standard and FM broad-
cast, shortwave, and VHF-TV
spectrums from 550 kc. to 220
me, in 6 bands.

It’s a compact, portable, rug-
ged, versatile instrument—engi-
neered and designed for most
efficient operation in practical
field use. It features a transistor-
ized power supply, meter indi-
cations proportional to carrier
streagth as well as sensitivity of
5 microvolts minimum for 5%
meter deflection over entire tun-
ing range.

For full details, send for bro-
chure IL-106,

SPRAGUE ELECTRIC COMPANY

35 Marshall Street, North Adoms, Mass.

SPRAGUE

32

THE MARK OF RELIABILITY

CIRCLE 32 ON READER SERVICE CARD

Members of the Project Oscar Association with their satellite

Hams Orbit Their Own Satellite

AMATEUR RADIO operators officially
got into the space business shortly
before noon on Dec. 12 when Oscar
(Orbiting Satellite Carrying Ama-
teur Radio), a ten-pound transmit-
ter, piggy-backed into space from
Vandenberg Air Force Base on Dis-
coverer 36.

Oscar separated shortly after-
wards to establish its own orbit.
Initial radio pick-up was made by
KC4USB, Marie Byrdland, at 1:08
PST as the satellite made its first
pass over the South Pole.

Continuing around the world, the
orbit’s second fix was established at
Kodiak, Alaska by KL7EDM at
2:08 PST. Subsequently, it
heard in the Hawaiian Islands and
again at the South Pole, establish-
ing that it was in its expected orbit.

Project Oscar, conceived and exe-
cuted by a group of radio amateurs
in the San Francisco Bay area, ulti-
mately aims at providing the
world’s hams with an international
satellite communications system to
back up conventional communica-
tions in time of emergency. First
satellite of the program is merely a
transmitter which beams out the
word HI at approximately 10 times
a minute. The group hopes to build
relay capabilities in future satel-
lites.

Oscar operates on a band of two
meters at a frequency of 145 Mc,
and puts out a 100 milliwatt beacon
signal. Expected life was three
weeks to one month. Hams with
sensitive receivers and high gain
antennas should be able to pick up
the signal as far away as one thou-

Was

sand miles. The American Radio
Relay League estimates that many
of the world’s 300,000 radio ama-
teurs are participating in tracking.

The satellite uses transistor oscil-
lator, power amplifiers and keyer.
The rate at which it sends its signal
is governed by a thermistor. Out-
side measurements of the satellite
are one ft square by six in. deep.
The mechanism which ejected the
satellite from its parent satellite
automatically turned on the trans-
mitter and erected the antenna.

Project Oscar was originated in
1959 by Donald Stoner, Alta Loma,
Calif. He was joined in the effort
by several engineers from various
California space and missile com-
panies. Director of field operations
for the project is Fred Hicks. Both
are employed by Lockheed Missile
and Space Division in Sunnyvale,
Calif.

All work on Oscar has been per-
formed by the group during off-
duty hours and funds for the effort
have been privately raised.

Satellite is a foot square and a
half-foot deep

electronics

MEETINGS AHEAD

RELIABILITY AND QUALITY CONTROL
Symposium, PGRQC of IRE, AIEE,
ASQC, EIA; aa Hilton Hotel,
Washington, D.C., Jan. 9-11, 1962.

OPTICAL CHARACTER RECOGNITION Sym-
posium, Nat. Bur. Stds.; Dept. of Int.
Aud., Wash., D.C., Jan. 15-17, 1962.

ELECTRICAL ENGINEERING
for electrical-electronics
AIEE; N.Y.
29-Feb. 2,

Exposition

industry,
Coliseum, N.Y.C., Jan.
1962.

REDUNDANCY TECHNIQUES FOR COMPUT-
ING SYSTEMS, Office of Naval Re-
search; Dept. of Interior Aud., Wash-
ington, D.C., Feb. 6-7, 1962.

MILITARY ELECTRONICS Convention
PGMIL of IRE; Ambassador Hotel,
Los Angeles, Feb. 7-9, 1962.

SOLID STATE CIRCUITS, Internat. Conf.,
PGCT of IRE, AIEE; Sheraton Hotel
and U. of Penn., Philadelphia, Pa.,
Feb. 14-16, 1962.

APPLICATION OF SWITCHING THEORY TO
SPACE TECHNOLOGY Symp., USAF,
Lockheed Missiles & Space; at Lock-
heed, Sunnyvale, Calif., Feb. 27-Mar. 1,
1962.

SCINTILLATION AND SEMICONDUCTOR
Counter Symp, PGNS of IRE, AIEE,
AEC, NBS; Shoreham Hotel, Wash-
ington, D.C., Mar. 1-3, 1962.

MISSILES & ROCKET TESTING Sympo-
sium, Armed Forces Communications
& Electronics Association; Coca Beach,
Fla., Mar. 6-8, 1962.

EXTRA-HIGH VOLTAGE COMMUNICATION,
CONTROL & RELAYING, AIEE; Baker
Hotel, Dallas, Tex., Mar. 14-16.

Coli-
New

IRE INTERNATIONAL CONVENTION,
seum & Waldorf Astoria Hotel,
York City, Mar. 26-29, 1962.

Clinie, Rochester
Univ. of Rochester,
Mar. 27, 1962.

QUALITY
Soc. for
Rochester,

CONTROL

Q.C.;
IN: ks

ENGINEERING ASPECTS OF MAGNETO-
HYDRODYNAMIcs, AIEE, IAS, IRE,
U. of Rochester; U. of Rochester,
Rochester, N.Y., Mar. 28-29, 1962.

SOUTHWEST

SHOW; Rice
April 11-13,

IRF
Hotel,
1962.

CONFERENCE
Houston,

AND
Texas,

JOINT COMPUTER CONFFRENCE, PGEC of
IRE, AIEE, ACM; Fairmont Hotel,
San Francisco, Calif., May 1-3, 1962.

HUMAN
PGHFE
May 3-4,

FACTORS in
of IRE;
1962.

Electronics,
Los Angeles, Calif.,

ELECTRONICS COMPONENTS CONFERENCE,
PGCP OF IRE, AIFE, FIA; Marriott Twin
Bridges Hotel, Washington, D.C., May
8-10, 1962.

NATIONAL AEROSPACE Electronics Con-
ference, PGANE of IRE; Biltmore
Hotel, Dayton, Ohio, May 14-16, 1962.

MICROWAVE Theory & Techniques Na-
tional Symposium, PGMTT of IRE;
Boulder, Colo., May 22-24, 1962.

December 29, 1961

Advertisement

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POOR TR Menage ge
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The Model 1W22 Volt-Second
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Products Division, is a_highly-
specialized instrument which gener-
ates a train of identical pulses.

The volt-second area of the pulses, |
continuously variable over a wide |
range, is accurately determined at
any time by multiplying the current
flowing through an associated pre-

square-loop core toroid undergoing
a pulse test.

The Model 1W22 is intended for
the calibration of electronic inte-
grators used in measuring the volt-
second areas of “‘fast’’ voltage pulses.
It is particularly useful in square-
loop core testing systems, including
cores such as bobbin, ferrite, and
small tape-wound cores.

The flux change in a core under
test is determined by integrating the
core output response with an elec-
tronic integrator. The output of the
integrator is proportional to the
flux change and can be expressed in
terms of volt-seconds or in equiv-
alent flux units, such as Maxwells.

The output of the calibrator con-
sists of uni-polar voltage pulses of
60 pps, each having a pulse width
of approximately 0.5 sec. The
actual volt-second area of each out-
put pulse from the calibrator mav
be varied, from 2.5 to 550 Maxwells,
continuously and precisely.

| Model 1W22, housed in a rugged
steel cabinet, is intended for bench
| use. Model 1W20, for standard rack
| mounting, is also available.

For complete technical data, write
for Engineering Bulletin 90,100 to
Technical Literature Section,
Sprague Electric Company, 35
Marshall St., North Adams, Mass.

CIRCLE 200 ON READER SERVICE CARD

cision ammeter by the calibration |
constant of the instrument. The wave | mums) which is far superior to any-
| shape of the pulses is similar to |

| those which are produced by a |

Head-and-Shoulders
Above Any Other
Core Driver on
the Market Today!

| Sprague Type 2N2100 Germanium

Electro-Chemical Diffused-Collector
Transistors, especially developed for

| high current core driver applications,

offer a combination of ratings (with
15 guaranteed minimums and maxi-

thing you've ever seen before.

ECDC construction combines the
optimum features of the electro-
chemical precision-etch techniques
and diffused-collector techniques in
one highly-mechanized process.
That’s why the 2N2100 meets all of
the conditions for an “ideal” transistor.

Compare these characteristics and
ratings with those of any other core
driver!

Ves —40v
Vees 35V
Ves -2V
—500ma

fre (min. at
lec

Sor: = 1.5V)
Vce (SAT)
(max. atic = 200ma
Ip = 10ma)
Vee (max. at
lc = 200ma
12ua at 15V te = 10ma)
40 at Cob (max.)
lc = 100ua fr
BVces (min.) 40 tr (nsec. max.)
BYVceo (min.) 20 ts (nsec. max.)
BV eso (min.) 4 tt (nsec. max.)

le
Pa (25°C
case)

Pa (25 €
ambient)
Iceo (max.)
BYceo (min.)

750mw
250mw

For complete technical information
on Type 2N2100 Transistors, write
for Engineering Bulletin 30,401 to
Technical Literature Section, Sprague
Electric Company, 35 Marshall Street,
North Adams, Massachusetts.

*Trademark of Sprague Electric Co.
RS rae

SPRAGUE

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CIRCLE 33 ON READER SERVICE CARD 33

Highly Reliable
HITACHI ‘‘SEMI-CONDU

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Switching Transistors and Diodes

Hitachi semi-conductors provide the
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34 CIRCLE 34 ON READER SERVICE CARD electronics

PULSE POINTERS -

SERVO modular serial word generators offer broad test
flexibility for digital circuitry and logic design

Servo’s fully transistorized modular
serial word generator standardizes
such features as variable sync bit loca-
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wide range of digital circuitry and
logic design problems.

Pulse and NRZ outputs allow use of
the equipment for generating variable
duration widths, coded logic levels for
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MODEL 5510

Fully modularized construction ena-
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A broad range of special digital
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STANDARD OUTPUTS — Set for seven bit word length, 1011100 data

__| clock | | | |

ee PT Le

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7

Ul LI

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NRZ

bes

Flexible basic design features:

® Clock Rate: Pulse spacing continu-
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2mce. to 100 cps
Syncs: Variable and delayed
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Word length selectable by two 10
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® Arbitrary coding

Clock output 0.2 usec wide, pos. 4.5v
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Complementary pulse output simul-
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NRZ

One of 33 cataloged instruments in
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Fill in coupon for details.

Servo Corporation of America
111 New South Road
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Gentlemen:

(] Please send detailed catalog.

‘om |

C) Please contact me for demonstration.

C) Please send me a free SERVO slide rule.

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Sales & service offices coast-to-coast * Representatives in major cities

single pulse generators - double pulse generators - word generators - pulse train and pulse code generators - time delay and gate generators + current generators and core testers - modules

December 29, 1961 CIRCLE 35 ON READER SERVICE CARD 35

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CIRCLE 36 ON READER SERVICE CARD

electronics

electronics

~ December 29,1961

o
«

~
-

FIG. 1—Partially disassembled
underwater object locator. Front
portion mounts transducer and
forms beam pattern. Compass pro-
vides directional information

Portable Sonar for Frogmen

Has a range of 120 yards with both active-search and passive-listen

modes. Range is presented as a variable audio tone

By I. R. COLLDEWEIH
E. L. WALLS
R. D. LEE

Dalmo-Victor,
Division of Textron Inc.,
Belmont, California

SCUBA (self contained underwater
breathing apparatus) swimmers
have always been handicapped in
their operations by limited under-
water visibility. Only in a few geo-
graphic areas is the water clear,
and even on bright days the usable
light from the sun extends only
about 50 feet below the ocean sur-
face. In muddy rivers and bays,
visibility is reduced to only a foot
or slightly more and underwater

December 29, 1961

searchlights are only a partial solu-
tion because they are extremely
limited in their application.

The portable underwater object
locator, shown partially disassem-
bled in Fig. 1, has been developed to
extend the scuba swimmers ability
to locate and identify submerged
objects within a range of 120 yards
regardless of water clarity. The
design provides for two modes of
operation; an active-search mode,
and a passive-listen mode capable
of receiving ultrasonic marker buoy
signals.

The

is a

underwater object locator
continuous-transmission fre-
quency-modulated sonar that pro-

duces a narrow, sharply-defined
acoustic beam. The output signal
is a linearly decreasing f-m signal
whose repetition period is deter-
mined by the range scale.
Returning echos from _ under-
water objects are heterodyned with
the transmitted signal and pre-
sented to the operator as an audio
tone in his water-tight headset.
The pitch of the tone indicates the
distance to the target; the lower
the tone, the nearer the operator is
to his object. A magnetic compass
that may be illuminated by press-
ing a button indicates direction.
Thus, the equipment provides both
range and bearing information to

37

SAWTOOTH
GEN

AMP

POST HEADSET
DRIVER

HEADSET

cTor| J

FEEDBACK CIRCUIT

Wl

FIG. 2—F-m oscillator is modulated by the sawtooth generator in the
search mode and by manual frequency control in the listen mode

—€\

E

TO BLANKING

+ 3V CIRCUITS

FIG. 3—Sawtooth generator uses a series of emitter followers to reduce
output impedance. Sawtooth period is determined by selection of resistor

the scuba diver operating it.

By positioning the active-listen-
ing control in the listen position,
the operator can use the under-
water object locator to locate
marker beacons transmitting in the
range of 30 to 40 Ke. The operator
manually tunes the local oscillator
until an audible signal is received.
The pitch of the tone is not an in-
dication of the distance to the
marker beacon, but the direction to
the marker buoy can still be de-
termined because of the beam pat-
tern of the receiving hydrophone.
The device is enclosed in a two-part
cast-aluminum water-tight housing.
The front portion of the housing is
an inverted right circular cone that
mounts the transducer and forms

38

the acoustic beam pattern. The
rear hemispherical portion of the
housing contains the printed-circuit
board and flashlight battery power
supply. The control knobs, headset
connectors, and an illuminated com-
pass are externally mounted on the
housing. Two large guide handles
are provided for aiming the equip-
ment while in operation. The ob-
ject locator is designed to be 3
pound buoyant when submerged to
provide for easy handling and di-
recting. Seals are used between the
case halves and shafts to prevent
water leakage into the equipment.
The set contains a leak detector to
provide an audible signal to the
operator in case of failure of the
water seals. Two water proof head-

sets provide for the operator and
a buddy swimmer.

Figure 2 is a block diagram of
the equipment. The sawtooth gen-
erator provides a linearly decreas-
ing voltage whose repetition rate
or period is a function of the range
scale. The sawtooth voltage is ap-
plied to a voltage sensitive multi-
vibrator or frequency-modulated
oscillator.

The multivibrator output is
amplified to drive the projector por-
tion of the transducer. The re-
ceiver consists of a balanced modu-
lator mixer, slope amplifier, post
amplifier, blanking amplifier and
headset driver. Signals received
from the hydrophone are hetero-
dyned with a sample of the trans-
mitted signal in the balanced modu-
lator, resulting in many sum and
difference frequencies. Only the
difference between the received and
transmitted frequency is used. The
echo signal traveling from the unit
to the target and return undergoes
a time delay resulting in the re-
ceived frequency being higher than
the transmitted frequency. The
greater the distance, the greater
the difference frequency and conse-
quently, the higher the tone pre-
sented to the operator. The rate
at which the frequencies are swept
in a sawtooth manner is adjusted to
permit the difference frequency to
be in the audible range for the three
range scales of 0-20, 0-60 and 0-120
yards. With experience, the oper-
ator becomes proficient in estimat-
ing target range, depending on the
scale in use.

In the listen mode of operation,
a manually controlled d-c voltage is
substituted for the sawtooth gener-
ator. Additional capacitance is
switched into the frequency-modu-
lated oscillator to allow the oper-
ator to tune over the frequency
range of 30 to 40 Ke. The power
amplifier, projector and blanking
amplifier are switched out of the
circuit as they are not used in the
listen mode.

One of the major problems in the
design of the underwater object
locator was to obtain an output fre-
quency which varies linearly with
time over the temperature range of
0 to 50 C and with variations in
battery voltage. Since the range
signal presented to the operator is
the instantaneous difference be-
tween the transmitted and received

electronics

signals, linearity of AF/AT is es-
sential to present accurate in-
formation as a trained operator can
detect linearity variations of less
than 1 percent. To achieve the re-
quired linearity, temperature com-
pensation was introduced in the
sawtooth generator and f-m oscil-
lator circuits. A schematic is shown
in Fig. 3.

The sawtooth period is controlled
by capacitor C, and resistor R,, R,
or R, as selected by the range
switch. Transistor Q, provides a
constant current to charge capaci-
tor C, The constant current
characteristic is achieved by main-
taining the base of transistor Q,
at a constant voltage obtained from
silicon diodes D, and D., operating
in a forward-biased condition.
Transistor Q, causes capacitor C,
to charge negatively while the ser-
ies of emitter follows, Q,, Q. and
Q, provide high input impedance
so that the base of transistor Q, will
not load the constant-current cir-
cuit. The output of this series of
emitter followers is obtained at the
emitter of Q, where the circuit im-
pedance is low. The output signal
from transistor Q, drives the fre-
quency-modulated oscillator and the
recycle circuit. The recycle circuit
blanks the transmitter output at the
end of each sawtooth period.

The frequency modulated oscil-
lator, is shown in Fig. 4. Emitter
follower Q, gives a high input im-
pedance while transistors Q, and Q,
operate as an astable multivibrator.

Acoustic energy traveling
through a water medium is attenu-

ated inversely as the fourth power
of distance traveled. The receiver
circuit has a sloping frequency-
gain characteristic to compensate
for this acoustic transmission loss
and effectively provide an output
signal level independent of range
to the target. A schematic diagram
of this portion of the receiver cir-
cuit is shown in Fig. 5. The re-
ceived signal from the hydrophone
is supplied to a balanced ring mixer
circuit. The instantaneous _ re-
ceived signal is mixed with the out-
going transmitted signal to produce
a difference signal whose frequency
lies in the range of 250 to 2,500 cps,
dependent upon the range to target.
This difference frequency signal is
applied to the base of the transis-
tor. The capacitor-inductor net-
work in the collector circuit pro-
vides the _ slope-frequency gain
characteristic. The design of this
network required consideration be
given to the frequency response of
the following amplifier stages, as
well as the headset response. The
net effect of the combination is to
produce a constant audible signal
level in the headset as the operator
swims toward a target. To accom-
plish this, the system response in-
creases approximately 10 db per
octave over the receiver frequency
range.

The leak detector consists of a
pair of wire electrodes extending
from the printed circuit board to
the lowest point in the case. Cur-
rent between the electrodes due to
salt-water conductivity provides a
regenerative feedback path around

TO DRIVER

the receiver audio amplifer circutts.
Entrance of only a few drops of
water is sufficient to complete the
circuit and cause the receiver to
oscillate at an audible frequency,
thus alerting the operator and pre-
venting extensive water damage.

The headset design uses a bone-
conduction element to withstand
the hydrostatic pressures encount-
ered at depths as great as 200 feet.
The elements are mounted in
molded Neoprene ear cushions
attached to a beryllium copper
headband. Waterproof quick-dis-
connect plugs provide for attach-
ment of the headsets. The acoustic
response of the elements provides
a rising frequency response char-
acteristic to compensate for the
target range, but cuts off sharply
above approximately 3,000 cps to
eliminate unwanted noise.

The transducer contains a series
of concentric rings of barium
titanate connected to form the
transmitting projector and receiv-
ing hydrophone. The hydrophone
consists of ten separate elements
and the projector six elements. The
projector is acoustically isolated
from the hydrophone by Coprene
rubber spacers. The crystal assem-
bly is encapsulated in a Rho-C ma-
terial to match to the acoustic im-
pedance of sea water, the entire
unit is protected by a rubber boot.

The underwater object locator
was conceived by engineers at the
U. S. Naval Electronics Labora-
tory, San Diego, California, who
constructed ‘several vacuum-tube
models for naval evaluation.

ia I
tit]

4 AMPLIFIER

FROM
SAWTOOTH
GENERATOR

FIG. 4—F-m oscillator can be placed in either the auto-
It is an astable multivibrator

matic or manual mode.

December 29, 1961

OUTPUT
SIGNAL
FROM
DRIVER

FIG. 5—Slope amplifier has frequency-gain characteristic
to make output level independent of range

39

Semiconductor Functional Blocks

THESE
blocks

SEMICONDUCTOR functional
perform multiplication or
division by a process similar to that

used by a slide-rule. Logarithmic
addition or subtraction, followed by
extraction of the antilogarithm,
gives the product or quotient of two
inputs. Forward-biased p-n junc-
tions provide the logarithmic rela-

tionship, because in the range
where the effects of series and
shunt resistances and saturation

current are negligible, diode volt-
age is directly proportional to the
logarithm of the current.
Functional blocks for multiplica-
tion were constructed to have an
input range of 10 to 1 and an out-
put range of 100 to 1. Accuracy
was within 5 percent at higher out-
puts, with a maximum error of
about 10 percent at the lowest out-
puts. Built-in temperature com-
_ pensation provides stable opera-
tion over a reasonable temperature
range without significantly increas-
ing the heat generated within the
block. By applying the same fab-
rication processing to uniform ma-
terial for all p-n junctions in each

40

block, diodes were produced with
identical electrical characteristics.

One functional-block design uses
an output transistor, rather than
an output diode. This modification
gives more useful power output
levels than can be obtained from
the all-diode block. Multiplication
accuracies of the transistor-output
blocks are not as good as with the
all-diode blocks.

When the logarithms of two
quantities are added, the sum is
equal to the logarithm of the prod-
uct. Thus, if Z = XY, then log Z =
log X + log Y.

The forward V-I/ (voltage-cur-
rent) characteristic of a_ typical
semiconductor p-n junction is loga-
rithmic over a considerable range.
Where diode series and shunt re-
sistance are negligible, the V-/
characteristic of a p-n junction can
be described by

I =I, (emer — 1) (1)

where 7 is the current, I, is theo-
retical saturation current, q is elec-
tron charge, V is the voltage across
the junction, k is Boltzmann’s con-

Diode and transistor
elements fabricated from
monolithic semiconductor

blocks form analog

multiplification

and division circuits

By H. C. LIN,
C. E. BENJAMIN,
P. W. SMITH,
B. S. ARONSON,

Central Research Labs.,
Westinghouse Electric Corp.,
Pittsburg, Pa.

stant, 7 is absolute temperature,
and vn is a constant involving vari-
ous physical processes in the junc-
tion region, with values from 1 to
greater than 3 for different junc-
tions.’ In the region where e‘’’"*’
>> 1, Eq. 1 can be expressed as

InJ/I, = qV/nkT (2)
Thus, if J is made proportional to
one of the quantities to be multi-
plied, V is proportional to the loga-
rithm of J.

The equivalent circuit of the
multiplier is shown in Fig. 1A. Di-
odes D, and D, convert input cur-
rents J, and 7, into logarithms V,
and V.. The sum voltage V, = V, +
V. is proportional to the logarithm
of the product /,J.. The antiloga-
rithm of V, is the current J, through
p-n junction diode D,.

For each diode D,,

Vn = (nkT/q) loge (1m/Tom) (3)
Therefore by adding the two loga-
rithms of the two inputs and taking
the logarithm of the output

Ts = (To3/To1 Lo2) Th 1 (4)

The analysis holds only for d-c

operation. For small-signal a-c

electronics

Perform Multiplication and Division

operation the addition of a-c volt-
age drops of known a-c currents
passing through diodes does not
yield a sum a-c voltage proportional
to the logarithm of the product.
This is due to a term proportional
to the sum of the inputs as well as
one proportional to their product,
and the former term is usually
larger than the latter.

Unfortunately, the d-c character-
istic of a semiconductor p-n junc-
tion is sensitive to temperature.
At room temperature, the J, of a
silicon diode will change by about
9 percent per deg C; this change is
approximately proportional to qE,/
nkT*, where E, is the energy gap
(1.1 ev in silicon).

In the expression for J, in Eq. 4,
the proportionality factor is equal
to I,3/1., J... Since all of the satura-
tion currents have the same tem-
perature coefficient, the quantity
I 4s/Io. Toe is as temperature sensitive
as any one saturation current alone,
that is, it will vary by about 9 per-
cent/deg C.

To compensate for this tempera-
ture variation, another p-n junc-
tion diode, D,, is introduced (Fig.
1B). If J,, J., J;, and J, are the for-
ward currents through the four re-
spective diodes, and /,,, I.., I.., and
I,, are the theoretical saturation
currents of these junctions, output
current J, can be shown to be

_ I tet hls :
I; = (i: i) x I (5)

Because the saturation currents all
have approximately the same tem-
perature coefficient, the quantity in
parentheses will not vary with tem-
perature. Thus if J, is held con-
stant, then /, will be proportional
to the product /,/J,. For best accu-
racy, good thermal coupling should
be maintained between the four di-
odes to equalize the temperature.
A monolithic structure provides in-
timate thermal coupling within the
semiconductor crystal.

For maximum accuracy inde-
pendent of temperature (7), both
(OV/0O log I); and (OV/0OT), must
remain constant. Measured curves
of V versus J as a function of T and

December 29, 1961

V versus T as a function of J for a
typical forward-biased diffused sili-
con diode are shown in Fig. 1C and
1D. These relationships hold except
at relatively high temperatures and
low currents. The diode whose
characteristics are shown has a
junction area of 0.19 square inches,
and would be used in a multiplier/
divider block as D,, D., or D, at rel-
atively high currents, to avoid op-
eration in the low-current range.
Smaller-area diodes, such as those
more commonly used in the func-
tional blocks, would not show devia-
tions such as shown in Fig. 1C and
1D until higher temperatures or
lower currents, because these devia-
tions are due to the —1 becoming
significant in Eq. 1; this effect be-
comes more pronounced with in-
creasing /,, and this current is di-

BD, V3yt Vi +V2

Ploue

(Cc)

100pu0
CURRENT

™)

DIODE VOLTAGE

rectly proportional to the area.

The arrangement of the junc-
tions shown in Fig. 1B involves
ohmic interconnections of ” regions
to p regions at points a and b. On
the other hand, in Fig. 1E all four
diodes are connected back-to-back
(p region connected to p region and
n region connected to n region),
and no external interconnections or
separate interconnection regions
are needed. For fabrication in a
monolithic block, this is the most
desirable arrangement, even though
no common connection is permitted
between the two input circuits.

If an appreciable portion of
either input current shuld flow
through the output branch instead
of the desired input diode, accuracy
would be impaired. Output current
I, in Eq. 5 would then be modified

Vv IN VOLTS

1
40 50 60 70 80 90
TEMPERATURE IN DEG C

DEVIATION DUE TO
SERIES RESISTANCE

DEVIATION DUE TO
SATURATION CURRENT

LOGARITHMIC RANGE

/
‘

"Shaaaaas DUE TO SHUNT RESISTANCE

(E) (F)

CURRENT (LOG I)

FIG. 1—Basic multiplier (A); with temperature-compensation diode added
(B). Curves for silicon diode in (C) and (D) are for V versus I and V
versus T, respectively. Configuration of diode multiplier in (E) aids fabri-
cation. V-I curve for typical Si diode (F)

41

DIODE VOLTS (Vv)

0.2

1

MONOLITHIC
BLOCK

=
|

MILLIVAC
VY }MV270
O-C pv

a
-
nn

(a) Z 5.

CURRENT {I)

(Cc)

ae

pon ee er a ee

FIG. 2—Construction and equivalent circuit (A) of 4-diode multiplier-divider; V-I characteristics of its diodes (B). Test
circuit for checking multiplication characteristics (C)

as

aie? (I, Is) (Is—1s)
n= (Feit) x Uti) ©

Equation 6 shows that for accurate
multiplication J, should be very
small compared with /,, J., and J,.

The specifications for ranges of
operating values were one decade
for each of the inputs and two dec-
ades for the output. Therefore,
since I, is derived from the current
‘sources for J,, J, and J,, J, should be
less than 1/100 that of J,, J, and J,
so that the loading effect is insig-
nificant. If we insert this require-
ment into Eq. 5 by making J, I.,
and J, = 100 J,, then Jus To/To. Ice
= 0.01. The saturation currents
I,, are proportional to the junc-
tion” areas of their respective di-
odes. If D,, D., and D, have equal
areas, Eq. 5 will be satisfied by
making the area of D, 1/100 that
of the other diodes.

All four diodes must exhibit the
desired V-I-T relationship over the
full ranges within which they will
operate. In a forward-biased p-n
junction, the V-log J proportionality
does not hold at low currents where
the operating current is small com-
pared to the saturation current
(that is, where e‘” ~ 1 in Eq. 1,
where * = q/nkT) or to the shunt
leakage current. Operation at
greater than approximately 0.2
volt (so that e“” >> 1) !s neces-
sary. To minimize effects of shunt-

42

leakage current, proper junction
fabrication techniques must be
used, along with mechanical protec-
tion and surface stabilization at
the junction periphery.

At high currents, the series re-
sistance predominates over the
logarithmic relationship, and the
voltage drop in this region is linear
rather than logarithmic. These ef-
fects are shown in Fig. 1F, where
log J is plotted against V for a typi-
cal silicon diode. For a diffused-
junction diode, a low series resist-
ance is obtained by making the
junction area (particularly D,)
large and the thickness and resis-
tivity of adjacent semiconductor
material low. The resistance of out-
put current meter, J, in Fig. 1E,
should be as small as possible.

It is important that all four di-
odes exhibit the same logarithmic
slope (dV/d log I). From Eq. 2 it
can be seen that the multiplication
operation

(h/To1) (I[2/To2) = Is/Tos (7)

is obtained by making
eFV1 y ekV2 = ekVs (8)
where * = q/nkT and is inversely
proportional to the logarithmic
slope. Therefore accuracy does not
depend on the value of *, as long as
it is identical for all of the diodes,
but if logarithmic slopes should
vary among the diodes in a block,
serious errors will be introduced.
Several basic physical phenomena

are involved in making x different
from the value of unity used in
Shockley’s original analysis of p-n
junctions.* Recombination within
the p-n junction space-charge re-
gion’ will produce adjacent por-
tions of the forward characteristic
with n = 1 and n = 2; however in
practice the distinction between
these regions is so obscure that a
considerable region often exists
with a value of n constant at some
value between 1 and 2. For more
abrupt junctions, internal field
emission’ will result in even higher
values of n and excessively high
values of J,. However, the struc-
tures have extremely graded junc-
tions, with correspondingly low
fields, and effects from this phe-
nomenon appear to be negligible.

For silicon diodes made by vari-
ous processes, logarithmic slopes
have been observed from 0.08 to
0.18/current decade, corresponding
to values of n from 1.3 to 3. How-
ever, by using uniform semiconduc-
tor material and processing all four
diodes identically, uniform loga-
rithmic characteristics can be con-
sistently obtained. All of the dif-
fused junctions used in multiplier/
divider functional blocks exhibited
logarithmic slopes of approximately
0.09 v/current decade, correspond-
ing to an n of 1.5.

Details of construction and the
equivalent circuit of the four-diode

electronics

multiplier/divider are shown in
Fig. 2A. The monolithic block was
fabricated from a wafer of low re-
sistivity silicon of overall dimen-
sions * in. x 2 in. x 0.006 in. The
block has a p and an n layer. Metal
foils are alloyed for ohmic contacts
and reduction of thermal resist-
ance. Region isolation is provided
by the troughs.

To determine the quality of a
completed multiplier, the forward
V-I characteristic of each diode was
measured for the four diodes of a
typical unit (Fig. 2B). Each diode
must be operated in a region of its
characteristic curve linear on this
graph. For diodes D, and D., a
straight line region of one current
decade is necessary; for D, two cur-
rent decades are required. The cur-
rent through D, is set to permit op-
eration of D. over its best two-
decade region, while allowing D,
and D, to operate at current levels
that are as high as possible. This
adjustment feature allows multi-
plier/divider functional blocks with
diodes of different characteristics
to be set for operation in their op-
timum regions without additional
circuits.

Inputs to D, and D. were 0.2 ma
to 2 ma, with D, driven from 1 ya
to 100ua. The current required for
D, is that which causes 1 ya of cur-
rent through D. when D, and D
each have a current of 0.2 ma. When
J, and J, are each 0.2 ma, V, and V
are each approximately 0.35, for a
total of 0.70. The voltage across D
should be about 0.24 to cause /, to
be 1 wa. Thus, bucking voltage V,
must be 0.70 — 0.24 = 0.46v. A
current through D, of 1.1 ma pro-
duces V,.

Multiplication characteristics
were checked in the circuit shown
in Fig. 2C. Each input current was
varied independently over its full
one-decade range, and output cur-
rent was monitored by the d-e mi-
crovoltmeter, which measures the
voltage drop resistor R,.
Output current, which is propor-
tional to the product of inputs /
and J., was then obtained by divid-
ing the measured voltage by the re-
sistance of R,.

Figure 2B shows that the d-c re-
sistance of D, at the bottom of the
operating range (1 pa) is 2.5 x 10°
ohms, and at the top of the operat-
ing range (100 pa) it is 4 x 10°
ohms. Therefore, the voltage drop

across

December 29, 1961

across R,, a 10-ohm resistor, is neg-
ligible.

The analog multiplier can be
used as an analog divider by having
the input currents fed to diodes D,
and D, of Fig. 2C. The combined
voltage is (V, — V,), a logarithmic
difference, corresponding to the
logarithm of the quotient in divi-
sion. Diode D, supplies the anti-
logarithm as /,, thus producing an
output current proportional to the
quotient of the input currents. Di-
ode D, is used for temperature com-
pensation and bias.

A typical unit exhibited division
accuracy within 5 percent for about
14 decades; at higher output cur-
rents series error was introduced

'

|

|

|

1

!

|
——_——
ot, MONOLITHIC

BLOCK

—Diode-transistor

Vy )

Pa. » multi-

plier-divider block and test circuit

as the output current became com-
parable to that of one of the inputs.
This problem is more serious with
dividers than with multipliers,
since in multiplication the maxi-
mum output current is obtained
only when both inputs are at their
maximum, with division
maximum output is obtained with
one of the inputs at its minimum.
Input diodes that are logarithmic
at higher currents would eliminate
this error.

As in multiplication, the output
diodes must be logarithmic
two decades if the inputs are al-
lowed to vary independently over
one decade each in division. Since
diodes D,, D., and D, all have the
same area in this design, the unit
can be used for either multiplica-
tion or division by interchanging
D, and D, for the input and tem-

whereas

over

perature-compensating.

The output information from the
four-diode multiplier/divider func-
tional block is difficult to work with
in practical circuits. Being a d-c
voltage in the microvolt range, such
information requires d-c amplifiers
to raise the output to a level that
can be used in the conventional cir-
cuits of computers or controls.
Since the transfer characteristic
of a transistor (Jwu.-V;,) is also
logarithmic, a transistor can be
substituted for the output diode of
a four-diode block (Fig. 3). Tran-
sistor output current /. is propor-
tional to the product of the two in-
put currents, requiring no auxiliary
circuits for practical applications.
This transistor is incorporated into
the monolithic block in place of the
output diode. The inherent current
gain of the transistor allows its
input current to be small enough to
be negligible with respect to the
input diode currents, while the out-
put current can be at usefully high
levels and is relatively insensitive
to load. The transfer characteristic
generally does not depend upon cur-
rent gain fall-off at low currents in
the transistor.

Multiplication accuracy of the al-
loyed emitter multiplier divider
block is good. Curves of V-J-T have
also been measured for the transfer
characteristics of transistors being
fabricated within multiplier ‘divider
blocks. Although the families of
curves are not as linear and parallel
as those for simple diodes, they are
of the same general character and
tend to provide the same tempera-
ture compensation.

The work described here
part of the Molecular Electronics
Program under Air Force Contract
AF33(600)-39378. The authors
thank E. M. Black and G. Machiko
for valuable assistance in fabrica-
tion and testing.

was

REFERENCES

(1) J. L. Moll, The Evolution of the
Theory for the Voltage-Current Character-
istics of P-N Junctions, Proc IRE, 46, p
1,076, June 1958.

(2) H. C. Lin and R. E. Crosby, Jr., A
Determination of Thermal Resistance of
Silicon Junction Devices, IRE Nat'l Conv
Record, 1957, part 3, p 22.

(3) W. Shockley, The Theory of P-N
Junctions in Semiconductors and P-N
Junction Transistors, BSTJ, 28, p 435,
July 1949

(4) C. T. Sah, R. N. Noyce, and W
Shockley, Carrier Generation and Recom-
bination in P-N Junction Characteristics,
Proc. IRE, 45, p 1,228, Sept. 1957.

(5) A. G. Chynoweth and K. G. McKay,
Internal Field Emission in Silicon P-N
Junctions, Phys Rev, 106, p 418, May 1957.

43

ILLUMINATION STABILIZER

for Photosensing System

Feedback circuit generates precise pulses to control light levels of light-sensitive devices that

use a lamp as the light source. Feedback loop obviates elaborate circuits usually associated with

switched control stabilizers

By J. R. DYKE,
Computer Developments Limited,
Middlesex, England

(A)

FIG. 1

? CONTROL :

ELEMENT

AMPLIFIER MEASURING

ELEMENT

REFERENCE

FOR RELIABLE OPERATION of the pho-
tovoltaic system in a punched-card
or punched-tape reader, the illumi-
nation level of the card at the read-
ing station should be constant.

Stability control includes lamp output in the feedback loop (A)
and uses transistor as a control element (B)

REFERENCE (SLICING)
LEVEL

TIME

nd
(A) OUTPUT FROM
PHOTOVOLTAIC CELL

TIME

(B) oirterence BETWEEN
CELL OUTPUT AND
REFERENCE AFTER
AMPLIFICATION

| IME

(C) wioth contRoLten
PULSES GENERATED BY
SLICING THE WAVEFORM
OF (B)

FIG. 2—Waveforms of pulses generated by light stabilizer

ag

Where the light source is a low-
voltage tungsten-filament lamp sup-
plied through a transformer from
the main power supply, constancy
of light output cannot be assumed.

Variations in illumination have
been due to variations in main
power supply and individual differ-
ences between bulbs, changed regu-
larly to avoid failures.

For a_ constant illumination
source, not affected by changing
bulbs, it is not enough to stabilize
the voltage across the bulb or the
current through the bulb, instead,
the feedback system must include
the light from the bulb in its con-
trol loop, see Fig. 1.

Photoelectric cells, already used
in the reading stations, were chosen
for measuring the _ illumination
level. Sensitivity of the cells is sub-
stantially independent of ambient
conditions, and they are rugged.

However, control for the lamp
current presented a problem. Mag-
netic devices were ruled out because
of weight, bulk and expense. Sili-
con controlled rectifiers were almost
as expensive, and required more
complex circuits. So transistor con-
trols were chosen.

In a simple control arrangement,
the base of a transistor may be sup-
plied with a steady control current,
or with pulses that switch the tran-
sistor on and off. A resistor placed

‘across the transistor reduces dissi-

pation and, in the switched system,
limits the peak voltage appearing
across the transistor. Less power is
dissipated in the transistor, espe-
cially if the switching rate is low,
but this usually requires a more

electronics

S2T! ZENER
REF DIODE

J
sal

N

P. Vv. CELL
FERRANTI MSI

FIG. 3—Complete circuit of stabilizer.

complex amplifying circuit to gen-
erate switching pulses of control-
lable width. Since a 48-watt bulb
was to be controlled, dissipation in
the transistor was important, so a
simple method for producing the
required pulse was devised.

Pulse generation of the stabiliz-
ing circuit (Fig. 3) is illustrated by
Fig. 2. Light output from the bulb
contains about 1 percent of 100-cps
ripple, which lags nearly 90 deg on
the 100 cps component of the sup-
ply to the bulb because the thermal
time constant of the filament is
much longer than 0.01 sec. The dif-
ference between the current from
the photovoltaic cell in Fig. 2A, and
the reference current, is amplified
to the waveform in Fig. 2B. Apply-
ing this pulse to a slicing transistor
(Q. in Fig. 3) produces the width-
controlled pulses of Fig. 2C. Pulse
widths of this train increase with
a reduction in the mean level of
illumination, so that after amplifi-
cation, these pulses drive the con-
trol transistor (Q, in Fig. 3).

The circuit is polarity sensitive,
not waveform sensitive. If the pho-
tocell is connected the wrong way,
feedback will be positive instead of
negative, and the light output will
not be stabilized.

In the stabilizer circuit, Fig. 3,
the reference current is supplied
from the Zener diode through R,
and R,,. The difference between this
current and the current from the
photovoltaic cell is amplified by Q
and applied to the base of Q.. These
pulses are amplified by Q,, Q, and
Q., and supplied to Q,.

The range over which the illumi-

December 29, 1961

—6.3V

Difference between reference current supplied by zener diode and current from
photocell is amplified by transistor chain, and then supplied to control element Q, to adjust lamp current

nation is stabilized extends from
the point where, with Q, conducting
all the time, there is only enough
current flowing to provide the re-
quired illumination—to the point
where, with Q, off all the time, too
much current will flow. This range
is determined by the transformer
secondary voltage, and the value of
R,,. The variation of illumination
over the controlled range is equal
to the percentage of ripple in the
output of the bulb, usually one per-
cent peak-to-peak.

Transistor Q, carries the full
lamp current when conducting but,
as it is saturated at this time, the
mean dissipation is low. This is an
important feature of the circuit.

The transformer power supply is
followed by a full-wave rectifier so
that the transistor deals with a
unidirectional current. Thus the
ripple problem is not aggravated by
half-wave action.

The photovoltaic cell is mounted
to obtain a mean short-circuit cur-
rent of approximately 1 ya at the
illumination level.

Nominal component values should
not exceed the following tolerances:
+5 percent variation of all resis-
tors except R, and R,,; +5 percent
variation in d-c supply voltages;
8 variation of GET872 transistors
down to 20; 8 variation of GET571
transistors down to 20 at a collector
current of one amp; 8 variation of
GET572 transistors down to 15, at
a collector current of 4 amp.

The dissipation in Q, is less than
2 watts; in Q., less than 200 mw.
In each of the other transistors,
dissipation is less than 10 mw.

Circuit stability is primarily de-
termined by the stability of the
reference current and of the photo-
cell sensitivity. Drift can be caused
by dust on the photocell or on part
of the lamp facing the photocell, or
by change in the leakage current of
Q,. The cell must be mounted so that
the sensitive area is not obscured
by dust, while Q, is selected for low
leakage. A silicon transistor can be
used only if the circuit is modified
to allow for the increased base-
emitter voltage required to drive
the silicon device.

The percentage of ripple in the
light output of the bulb is the main
factor determining the precision of
the system. Since precision is in-
versely proportional to the percent-
age ripple, precision may be in-
creased by smoothing slightly the
output from the rectifier, or using
a bulb with a longer time constant.

Precision is also dependent on
the effectiveness of Q, in controlling
the filament current. This is op-
timum if Q, is arranged to be
switched off during the time when
the voltage from the rectifier is
maximum. This operation, which
also minimizes the ripple in the
light from the bulb, is secured auto-
matically because of the 90-deg
phase lag introduced by the long
thermal time constant of filament.

Effectiveness of control may be
improved by increasing the value of
R,,, but this increases switching
losses in Q,. The precision of the
system is independent of the gain
of the transistors, providing this
gain is sufficient to secure rapid
switching of Q,.

DIGITAL CIRCUITS

Achieve Automatic Control

of Radar Range Tracking

Tracking modern high-speed targets imposes tremendous demands
on radar systems. This digital system locks its range gate onto

the target and holds it there, adjusting the range gate with every

target movement, and producing a highly accurate range readout

By DARRELL L. NEPVEUX, Advanced Electronics Center, General Electric Co., Ithaca, N. Y.

ACCELERATION
COMMAND

“TRACKING GATE
(B)

FIG. 1—Only one ranging counter is shown in digital range tracking sys-

. tem (A). Pulse diagram (B) indicates relationship of tracking gate to main

46

bang

ALTHOUGH modern long-range sys-
tems bear a basic resemblance to
their ancestors, many new and mod-
ified techniques have been made
necessary by the extended require-
ments of such systems. In first
generation radars it was sufficient
to look with the receiver system at
any and all video returns between
two radar transmission pulses.
Range data was processed by the
operator noting the track of a spe-
cific video return pulse on a ppi cro.
In using modern long-range radars,
such techniques are no longer feasi-
ble for these reasons: although
radar range has been greatly ex-
tended, the video of interest is
normally confined to a small seg-
ment of overall range; the ex-
tended range usually requires a
round-trip propagation time that
extends over several interpulse
periods of the radar prf. Due to
the high performance capabilities
of targets automatic tracking of

electronics

7" i PBR woe!
Fe

a |

-

=
E

‘At Ac
eA Ae 2

t
:

tae
a -

‘

¥..._ A...
YE...

.
4

ae NS

4

Master display and control console for pincushion radar set contains digital range tracking system, which is in cabinet

at right of operator

target-return video is necessary.

This article describes a digital
automatic range-tracking system
that tracks a single target or cluster
of targets. The system defines range
by surrounding a video (or group of
video) return(s) with a tracking
gate (Fig.1). A tracking gate may
be manually c~ automatically placed
or moved tc any position within
overall range. In typical operation,
the operator first cranks range in-
formation into the system and then
automatic tracking takes over the
control of the tracking gate, which
then follows the target through
every range change.

To obtain accuracy and resolu-
tion in range control, the control
functions are implemented by
digital logic and circuits. The
range value (in ft) of a single
binary bit in a digital system is
derived from: ft of range/bit =

propagation velocity

“2 x clock frequency |

December 29, 1961

Thus, maximum range of the sys-
tem is prescribed by a sequence of
binary-arithmetic bits. The range
value of a single binary bit deter-
mines the maximum bit length of
the binary sequence that is neces-
sary to provide the maximum range
of the system. Any point within
the range is resolved to the ac-
curacy allowed by the range value
of a single binary bit. Placing the
tracking gate in a range position
is accomplished by counting out a
specific binary number and relating
the elapsed time of the count to the
predetermined point in range.
The tracking gate is moved by
changing the binary number, either
manually or automatically.

In Fig. 1A, the ranging counter
controls the R (or range) param-
eter (Fig. 1B) and the tracking
gate width counter controls the W
(or gate width) parameter. The
video-integrator-difference detector
block and the tracking loop provide

the automatic movement of the
tracking gate by changing R; a
manual input to control R is also
shown.

The primary components of the
system are the ranging counter and
the memory counter. In operation,
digital range information goes
from the memory counter to the
ranging counter, which then counts
clock pulses.

The memory counter is the
binary storage area, which con-
tains at all times the digital equiv-
alent of range R (Fig. 1B). It
is a static counter, since the only
allowable changes in its content
are controlled by the operator’s
variable control or the automatic
tracking loop input. Maximum
operating speed of the memory
counter is dictated by the maxi-
mum rate at which corrections in
binary value of range are to be
made. This speed is nominally an
order of magnitude less than the

47

LOGIC
OuTPUT ™

DIODES 0;,02, 03, 04,05
& Dg ARE IN65S9'S
K=X 1,000

GATING
OUTPUT

y iN277

GATING
LINE

CLOCK /
TRIGGER LINE
LINE

RESET

FIG. 2—High-speed buffered flip-flop of ranging counter

clock frequency. The memory
counter is a_ reversible counter
since both an increase and decrease
_in decimal range must be _ per-
mitted. Binary range information
held by the memory counter goes
to external processors or recorders,
as well as to the ranging counter.

Generation of a signal pulse that
indicates the beginning of the
tracking gate is performed by the
ranging counter. This counter is
an n-Stage shift register, which can
count to the maximum value of
range, and operates at the system
clock frequency. Counting in this
unit is done dynamically. The unit
begins to count clock pulses at the
appearance of a radar transmission
pulse and continues to count until
a number of clock pulses equivalent
to the decimal range has been
ceunted. At this point, it generates
a signal pulse which starts the
tracking gate.

To provide a high range-resolu-
tion capability, the clock pulse fre-
quency is high. Clock frequencies
in the 1 to 10 Me range are usually
specified. These clock pulses are
counted in the ranging counter,
which is composed of a series of
transistor flip-flop stages. The first
stage of this register must there-
fore count at the rate of the sys-
tem clock. This stage, a high-speed
buffered flip-flop, is shown in Fig.
2. Buffering is used in this circuit
to increase the load-handling cap-

48

ability and maintain
operating speed.

The counting technique in this
portion of the system provides the
least complicated performance of
the ranging counter. The technique
allows the ranging counter to start
from a preloaded condition with the
restraint that the number of clock
pulses necessary to take the counter
from its preloaded condition to its
full condition (when all of its
stages are in the ONE state) is
equivalent to the decimal range.
This restraint is met by taking the
complement of the decimal range
and preloading this into the rang-
ing counter. Since the decimal
range value is contained in a
parallel binary form in the memory
counter, it is simple to complement
each digit of this binary number
and preload the complemented
decimal range into the ranging
couniers. The ranging counter
can then be turned on by the trans-
mission pulse (main bang) of the
radar, count clock pulses until it
reaches a full count, then generate
a carry pulse that fixes the location
(in time, relative to the radar
transmission pulse used to start the
counter) of the tracking gate. The
ranging counter functions as an
asynchronous counter having a
high-speed counting capability in
its first few stages. Although the
ranging counter functions asyn-
chronously as a unit, its first few

the high

stages run synchronously (this was
required to implement another
function).

Since the ranging counter tabu-
lates the elapsed time between a
main bang and the desired begin-
ning of the tracking gate, it is
necessary to use the main bang to
initiate counting in the ranging
counter. However, the maximum
range of the radar may include
several interpulse periods of the
radar prf. Therefore, there must
be sorting or counting of radar
main bangs before they are used
with the ranging counters.

Figure 3 shows how this is per-
formed. The radar main bangs
are accepted into the system seri-
ally, on a single line. System spe-
cifications dictated the number
(m) of the parallel ranging count-
ers necessary to cover the maxi-
mum range. Each counter is
started sequentially, in the 1
m sequence, by a main bang. Only
a single such ranging counter ap-
pears in Fig. 3. The main bangs
are divided in a 1/m counter to
provide the sorting, with one main
bang being fed to each ranging
counter in sequence. Each main
bang sets a_ start-stop flip-flop
which, when set, opens a clock gate
allowing clock pulses into the rang-
ing counter which has been pre-
loaded. (There are m flip-flops,
clock gates and ranging counters.)
On reaching a full condition, the
ranging counter generates a carry
pulse which resets the flip-flop,
closing the clock gate and putting
the ranging counter in condition
to accept the next preloading of
complemented decimal range. All

RANGING COUNTER

(n STAGES)

OCcK

L
TRIGGER GATING
LINE

BANGS

FIG. 3—Inputs and outputs identi-
fied as 2 to m would go to other
ranging counters that are not
shown

electronics

INVERTER

AMPL

TRACKING GATE

(HALF INVERTED)

INTEGRATOR

| GATE OR
Q.

2
2N706

FIG. 4—Output of this video integrator

preloading is accomplished at the
command of a trigger pulse that
occurs at some convenient time
previous to the main bang used
with the ranging counter.

The carry pulse generated by the
ranging counter is now positioned
in time at the point where, the
tracking gate will begin. Since
each of the m ranging counters

provides a carry pulse, and these
occur in a serial time sequence, the
OR bléck combines all of the carry

pulses on a single line, and delivers
tracking gate triggers to the track-
ing gate width control.

The tracking gate triggers are
generated at a rate equivalent to
the radar prf. If the information
contained in the memory counter is
not changed, the position of the
tracking gate will not change.

The tracking gate width control
provides some video return pulse
selectivity and allows for the dis-
persion of video pulses over a pre-
determined range increment. The
technique that provides this con-
trol is identical to the technique
that provides tracking gate place-
ment. The operator throws a
switch that supplies information, in
parallel binary form, that deter-
mines the width of the tracking
gate. Since it is proper to expect
the same resolution of the tracking
gate width as obtained in the place-
ment of the tracking gate, the
range value of a single binary bit
is identical to its value in the rang-
ing counter, and the same clock
frequency is used. Since the gate
width counter is triggered at the

December 29, 1961

goes to difference detector

radar prf rate, only one such unit is
necessary.

The memory counter controls the
location of the tracking gate. In-
formation is stored in the memory
counter in binary form; therefore,
all changes inserted into the mem-
ory counter must be in binary form.
To comply with the requirements
of the system, changes in the con-
tents of the memory counter are
allowed in two modes: manual and
automatic.

The method used in the manual
mode is range-rate control and is
the one preferred from a human-
factors standpoint. The operator
has one control that controls the
frequency of a pulse source fed into
the memory counter. Operating at
any one frequency results in a con-
stant rate of change of range, since
a constant stream of pulses is fed
into the memory counter, each
pulse representing a single binary
bit value of range. This method
presents the advantage to the oper-
ator of continuous control over
movement of the range parameter
without physical action, with the
disadvantage of requiring a second
source of information on the value
of absolute range. This disad-
vantage is overcome by providing
a decimal readout of the range
value.

The automatic control of infor-
mation entered into the memory
counter is determined by the track-
ing loop. The requirement placed
upon the system in the automatic
tracking mode is that it maintain
a predefined spatial relationship be-

tween a single video, or group of
video, and the tracking gate, under
specified conditions of target-
return video velocity and accelera-
tion. This requirement means that
the tracking gate is centered on the
video pulses appearing within its
limits.

The operation of defining the
center of the tracking gate is per-
formed in the tracking gate di-
vision block. This block receives
manual gate width control informa-
tion. The tracking gate division
block contains a binary shift regis-
ter into which this parallel-binary
gate-width information is fed. The
size of this shift register is such
that the least significant binary
digit of the width of the tracking
gate is not entered into the regis-
ter. Thus, a binary division by
two is performed and counting out
this register with clock pulses will
-ause a carry pulse to be generated
at the center of the tracking gate.
The center of the gate is defined
to a resolution of one bit value of
range. The other inputs to this
division block are the tracking gate
trigger (indicates the beginning of
a tracking gate), the carry pulse
from the tracking gate width
counter (indicates the end of a
tracking gate), and the system
clock. The outputs of the division
block are three pulses, indicating
the beginning, center, and end of
the tracking gate.

Since the tracking-gate center is
defined, it is possible to determine
the video contents of each half of
the tracking gate. To restrict the

49

influence of noise on the tracking
loop, a video-signal-plus-noise-inte-
gration method was used. The
triggers of the tracking-gate-divi-
sion block open two separate but
identical integrator circuits. One
of these integrator circuits is
shown in Fig. 4. The first inte-
grator accepts all of the video and
noise signals within the first half
of the tracking gate and performs
a voltage-time integration, which
yields a certain result. The second
integrator performs a similar func-
tion to the interval of time inclosed
by the second half of the tracking
gate. The results of these two
integrations are then compared,
providing two possible conditions:
first, the two volt-time integrations
yield identical results which means
that either there is no video in the
tracking gate or that it is properly
centered; second, the integrations
are not identical, which provides
an error signal of proper polarity
to cause the tracking gate to center
on the video. Performing the inte-

gration function on the raw video
and noise
effects
peaks.

reduces the random
introduced by the noise
The output of the video
integrator and difference block is
an error signal of proper polarity
for use with the remaining com-
ponents of the tracking loop.

The input to the tracking loop
indicates the position of the video
that must be tracked (it is in one
of two halves of the tracking
gate); at the other end of the loop
is the memory counter. The rang-
ing counter, tracking gate width
counter, and tracking gate division
components have no effect on the
tracking dynamics, since their in-
fluence is contained within a single
tracking period, (where tracking
period is defined as the time be-
tween two adjacent main bangs).
The memory counter, however, has
a continuing effect on the tracking
loop. Operating as a digital com-
ponent, it is a position integrator.

The analysis begins from the
tracking gate position. This is the
contents of the memory-counter
position integrator (since a paral-
lel binary format is used). The
position integrator is a binary shift
register that accepts binary correc-
tions and performs a binary inte-
gration of these corrections. Thus,

50

on a long-term basis, the correc-
tions provided to the position inte-
grator must be a true indication of
the velocity of the video being
tracked; for example, video target
pulses with constant velocity can be
successfully tracked only if a con-
stant number of range unit correc-
tions are entered into the position
integrator at the initiation of each
cycle.

Some measure of tracked velocity
must be obtained from the preced-
ing components of the tracking loop
for use with the position inte-
grator. This uses the velocity inte-
grator and stabilization network.
The error signal output of the video
integrator and difference detector
is used as an acceleration command
to the tracking loop. An integra-
tion of these commands provides
the tracked velocity information.
This integration is performed in
the velocity integrator. If a Bode
diagram is drawn for the system,
it would show the single, 40-db-per-
decade slope caused by the two inte-
grators in the loop, the position
integrator and the velocity inte-
grator. Since the zero-gain line is
crossed at a slope of 40 db per
decade, the system will not appear
to be stable. This is the reason for
the inclusion of the stabilization
network, a lead network which
provides an overall Bode diagram
with a 20-db-per-decade slope at
the zero-db crossover point.

The operations that must be
performed by the velocity inte-
grator and stabilization network on
the error signal to yield the proper
inputs to the memory counter (posi-
tion integrator) can be implemented
in either an analog or digital man-
ner. The analog implementation,
the least complicated of the
two, requires conversion of the
error signal pulses to an analog
quantity. The integrator is a ca-
pacitor and the stabilization net-
work is a resistor-capacitor com-
bination providing a wide range for
selection of time constants. Digital
implementation of the integrator
is similar to that of the position
integrator and can use the error
signal pulses directly. The digital
stabilization network is more com-
plicated to provide the proper
range of time constants.

The velocity performance of this

digital tracking system in the auto-
matic tracking mode is a direct
function of the maximum number
of correction pulses that may be
entered into the memory counter
in one correction cycle, the number
of correction cycles in one second
and the range value of one correc-
tion pulse. This last quantity is
determined by the system clock
frequency. Since the _ tracking
gates are generated at the prf rate
of the radar, the correction cycles
per second will be equal to the
radar prf. Therefore, the only
parameter available for specifica-
tion is the number of correction
pulses per correction cycle, a quan-
tity easily manipulated to meet
system specification.

A similar approach yields infor-
mation on the acceleration per-
formance of the tracking loop. The
important consideration is the time
rate of change of velocity. In de-
termining this factor, the weight-
ing of the acceleration command
and the time constants of the sta-
bilization network are of prime
importance. It is relatively simple
to make changes in the velocity and
acceleration capability of the track-
ing loop. This is due to the digital
nature of the data being processed
in the tracking loop.

The system described above is
truly minimal. A complete digital
range tracking system would have
many necessary and useful aux-
iliary functions not mentioned. A
few of these are visual range dis-
plays and display triggers, auto-
matic radar prf control, provisions
for multiple tracking gates, auto-
matic coasting on loss of video,
and rate-aided manual acquisition.
While these functions require
extension and modification of some
of the techniques covered, the
components and techniques that are
described are the primary require-
ments of a digital range tracking
system.

The digital range tracking sys-
tem described has been designed
and built, and is operational as a
component of the Pincushion Radar
system. This effort was part of a
contract from the Advanced Re-
search Projects Agency, as a proj-
ect of RADC. The work was done
on a subcontract for Raytheon, Inc.
on the Pincushion Radar Project.

electronics

CAMERA PERISCOPE FOR

Cathode-Ray Tube Photography

Design of optics for photographing a crt display is straight

forward. An engineer working on the electronic system

complete the task by following explanation presented here

By DANIEL LEVINE,

Staff Scientist Lockheed Missile

and Space Co., Sunnyvale, Calif.
IN PHOTOGRAPHING a radar, tele-
vision or oscilloscope display, the
camera may either be in-line with
the cathode-ray tube, or the light
path many be folded in a camera
periscope, see Fig 1 (left). The
latter arrangement is widely em-
ployed to obtain more compact
packaging or to permit simultan-
eous viewing of the display by use

of beam splitters. The following ex-
planation eliminates tedious com-
putations in periscope design.

In Fig 1 (top center) the tri-
angle represents a cross section of
the outer limit of the cone of light
between the crt face plate on the
right and outer lens element on the
left. All rays which enter the
camera lens from the phosphor lie
within this cone. It is important
to note that the distance from the
tube to the apex of the cone is not

A--4 CAMERA
!

| CRT

!
¢-----[ >

OUTER LENS
ELEMENT

PLANE OF PERISCOPE MIRROR

equal to the distance from lens to
object used in the lens equation.
The distance L, between the front
lens element and the crt must be
measured on an experimental mock-
up, or else computed by means of
the lens equation with allowance
made for the length of the lens.
Then the height of the cone, L, is
determined by similar triéngles: as
seen in Fig. 1 (top center). Then
B= L, Ly Pu

= or L = (1)
Pu PL Py ~ PL

15
a IN DEGREES

FIG. 1—Alternative arrangements (left) for photographing a display: (A) single bend, (B) folded optical path, (C) off-
set camera indicator. The bounding cone (top center) is determined by the active sweep on the crt and the outer
lens limit. Periscope installation (bottom center) between camera and ert with view of the elliptical intercept. Axes

of the ellipse are at right

December 29, 1961

51

10 5 20
a DEGREES ——>
FIG. 2—Displacement of the center
of the ellipse from the optical axis

OUTER APEX
LENS

OF
cm: CONE

DIMENSIONS
IN INCHES

"IG. 3—Periscope design

2

Bae LENS

ELEMENT
7 FACE
(A) = 0.3 IN OF CRT

LOWER

REFLECTOR REFLECTOR

the cone semi-angle, denoted bya, is
equated as,

=_, Om
a = tan L (2)
The function of a periscope mir-
ror is to bend all the light rays in
the cone of Fig 1 (top center)
through an angle of 90 deg. Thus,
the sketch of Fig 1 (bottom center)
reproduces the bounding cone of
light, that has an elliptical inter-
cept with the plane of the periscope
mirror. This ellipse is the smallest
surface that can reflect all the
usable light emitted by the ert.
When it crosses the optical axis a
distance L, from the apex of the
cone, its semi-axes are

a Vv 2 tana
= 3)
L, 1 — tanta (
b 1

-_ —_ (4)
L, Vv cot?a — 1

so that the axial ratio is
a 2 3
b- V 1 — tan’a °)
In Fig 1 (bottom center), the
center of the ellipse is not on the

optical axis, but displaced x..
The offset distance is,

, 1/9 b

» > Vv « 9 +)
- =wvV2 (¢

Ly cota — 1 ({:) ;

The axial values may be read
from the graph of Fig 1 (right),
while the offset between the center
of the ellipse and the optical axis
is plotted in Fig 2.

As an example, a 5-inch ert with
a usable sweep length of 4.6 inches
is to be photographed with a 35-mm
F/2.3 lens, and the measured value
of L, for the desired image size is
12.20 inches. A two-reflector peri-
scope to fold the optical path as in
Fig 1B (left) is to be designed,
with the mirrors at 4 and 9 inches
from the tube face. Find the di-
mensions of the reflective surfaces
and their offset distances for
mounting purposes.

First Method:

The diameter of the aperture of
an F’/2.3 lens is equal to that of the
front lens element when it is wide
open. Consequently, the radius is

Maximum diameter ns

PL = o (7)
- Focal length
2 (F-number of lens)

35

L= 5 @3) = 7.6mm = 0.3 in.

Then Eqs (i) and (2) lead to

(12.2) (2.3)

L _ 9 = 14 in.

os
14

(right) and Fig 2,

@ = tan" = 9.3 deg

from Fig 1

a )
[ee

The two values of L, (which is
the distance from the apex of the
cone to the reflector measured along
the optical axis, are 10 and 5 inches.
The corresponding mirrors have
the design values:

= 0.167; i = 0.040.

a, = 2.40 in.; bh) = 1.67 in.; x2.. = 0.40 in.;
a. = 1.20 in.; be = 0.84 in.; r,.2 = 0.20 in.
The essential periscope dimen-
sions are drawn to scale in Fig 3.
The physical structure often is
much larger than the bounding cone
near the camera in order to retain
good mechanical strength. When
this is the case, light baffles with
inner radii only slightly larger
than this cone should be inserted
in order to reduce the stray light.
The periscope reflectors should not
be much larger than the minimum
dimensions.
Second Method:

After computing p, by means of
Eq (7), the tube face and outer lens
element are drawn to scale with the
known distance between them, as in
Fig 4A. The triangle determined
by these two line segments is then
completed, and lines at 45 deg are
inserted at the reflector positions on
the optical axis, as in Fig 4B. This
figure represents a cross section of
the light cone before the reflectors
are actually inserted to fold the
light path. Consequently, the major
axes of the ellipses and the offset
distances can be measured directly
on the scale drawing. The minor
axes are found from the axial ratio
of Fig 1 (right), which shows that
for a = 9.3 deg,

a

lies 1.434
Alternatively, the minor axes may
be found by rearranging Eq (6):

- ms 1/2
b [ * | - 0.8409 V x. L,
v2

The results, of course, are iden-
tical to those of the first method.
In general, the second method is
faster and slightly more accurate
when the drawing scale is large.

electronics

NEWEST

in the most
extensive line
in the industry

CENTRALAB

CERAMIC

TRIMMER
CAPACITORS

THAT MEET

MILC-81A

825 SERIES ACTUAL SIZE

Rated at 600 VDCW, 1500
VDCT, these units are well
within MIL specifications for
change in capacity under
temperature and vibration
extremes. Available in NPO,
N300, N500 and N650 tem-
perature coefficients in all
standard capacity ranges.

TEMPERATURE
CHARACTERISTIC

CAPACITANCE
RANGE (MMF)

CRL

MIL
LETTER

MIL
CRL |NUMBER'

NPO

A

070

N300

120

N500

130

B
Cc
D

200
250
300

450

MICRO-MINIATURE ACTUAL SIZE

Rated at 100 VDCW, 250 VDCT, this unit measures
only 0.201” in diameter and can be supplied on a
ceramic base plate, to your specifications, as small as
0.25” square, plus leads or mounting. It is available in
the following ranges: 1.5 to 5 mmf, 3 to 10 mmf,

and 7.5 to 25 mmf.

For detailed information on these and many other trimmer
and special ceramic capacitors, write for Engineering

Bulletin Group ‘‘C."’

D-6118

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ELECTRONIC SWITCHES « VARIABLE RESISTORS « CERAMIC CAPACITORS « PACKAGED ELECTRONIC CIRCUITS ¢ ENGINEERED CERAMICS

December 29,

1961

CIRCLE 53 ON READER SERVICE CARD 53

RESEARCH AND DEVELOPMENT

Powerful Vhf Radar Probes Sun’s Corona

Half megawatt radar and 1,024-dipole antenna array are gathering data

about solar phenomena

LONG-TERM STUDY of radar echoes
from the sun is providing valuable
scientific information. The continu-
ing systematic experiments could
improve prediction of solar activity
to avoid interruptions to radio com-
munications and reduce hazards to
space exploration.

The detailed study covers 32
radar measurements made during
an eleven-week period from April
19 to July 7 near El Campo, Tex.
Lincoln Laboratory of MIT is con-
ducting the project with joint U.S.
Army, Navy and Air Force support.
Although the first radar contacts
with the sun were made by Stan-
ford in April 1959, these are the
first regular measurements over an
extended period.

Scientific Data Provided

Radar studies provide valuable
information about the _ corona,
which ejects huge showers of high-
energy particles during sunspot ac-
tivity. The particles cause interrup-
tions of communications and
present one of the most serious
hazards to space travel. With radio
and optical techniques, radar can

54

improve warning of these out-
bursts, measure their location and
intensity and possibly predict them.
One indication of the tests is that
the sun is 50 to 100 times less capa-
ble of reflecting radio waves than
reported by Stanford. However re-
flectivity increased up to 50 times
in later individual tests when solar
activity was much more _ pro-
nounced. Also these measurements
are being made at 38.25 Mc, while
those of Stanford were made at 26
Mc where reflectivity may be
greater. These differences indicate
the wide variations in solar phe-
nomena associated with radar re-
flections and the valuable informa-
tion that radar can provide.
Thickness of the _ irregularly
shaped corona as observed by radar
is comparable to the visible ball of
the sun, called the photosphere. Re-
flection (radar cross section) de-
pends on size of the reflecting ob-
ject and its reflecting efficiency.
Although apparent diameter of the
corona at these frequencies exceeds
1.5 million miles, average cross sec-
tion in the experiments appears to
be only a few hundredths the size

of the photosphere. This low reflec-
tivity indicates the extent that
radio waves penetrating into the
corona are absorbed.

Measured cross section at this
frequency is substantially less than
had been calculated from theoretical
models, which are based on assump-
tions made without detailed infor-
mation. One assumption is that elec-
tron temperature in the corona is
about 1 million degrees C. If tem-
perature were assumed to be one-
half million degrees, theoretical
cross section for a quiet sun would
be much closer to that measured.

Effective size and shape of the
corona and its changing reflectivity
with sunspot activity can be studied
systematically with radar. Present
observations of a quiet sun indicate
that radar echoes were obtained up
to a half million miles from the
photosphere. The great fluctuations
in effective size, shape and intensity
of the corona expected because of
violent solar activity have already
been observed. Long-term radar ob-
servations will yield quantitative
data about these phenomena.

Radar Penetrates Corona

Radar reflections frtm the sun
are unlike those reflected from solid
objects that permit precise range
measurements. Signals penetrate
the gases of the corona distributing
reflections over the depth. This phe-
nomenon combined with the turbu-
lence and irregular shape produce
complex radar returns that enable
radar studies to obtain data about
the nature and extent of electrical
phenomena and disturbances.

Violent activity associated with
sunspots causes large clouds of
high-energy particles to be ejected
from the corona that interact with
the ionosphere and disrupt radio
communications. The effect occurs
about 18 hours after the solar ac-
tivity has been detected. These
clouds, which are a menace to space
flight, are sometimes sufficiently in-
tense to damage or destroy elec-
tronic instruments in space probes.
Systematic radar observations can

electronics

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December 29, 1961 CIRCLE 55 ON READER SERVICE CARD 55

simple, low-cost
way to increase
equipment

Patented

ie ; t-dis: ipating Electronic Tube

ge

= | A
obits 5

ee replacement costs due to t
way to meet your MTBF reliability contract requirements is to
start with the tubes — it costs so little to make them ‘“‘TR safe’’!

_

WRITE TODAY FOR IERC TR TECH BULLETIN NO. 1121.

IERCES.ovisicw,

international Electronic Research Corporation
135 West Magnolia Boulevard, Burbank, California

Foreign Manufacturers: Europelec, Paris, France. Garrard Mfg. & Eng. Co., Ltd., Swincion, England

56 CIRCLE 56 ON READER SERVICE CARD

be a valuable supplement to radio
and optical methods for studying
the nature, scale and frequency of
these disturbances.

The radar transmitter provides
0.5 megawatt continuous output. It
feeds an array of 1,024 dipoles in 8
rows 15 feet apart and about 4 mile
long. The fan-shaped beam is 15 de-
grees in the east-west direction and
} degree in the north-south direc-
tion. It is aimed by adjustment of
the individual dipoles.

Since the photosphere subtends
an angle of about 0.5 degree viewed
from the earth, beam thickness per-
mits observation of the photosphere
and the surrounding corona. The
sun travels from east to west along
the 15-degree beam width in a little
over a half hour, which is the time
for a complete radar run. The radar
transmits continuously for 16 min-
utes, which is the round-trip time of
sun-reflected signals. After 16 min-
utes when signals begin to return,
the transmitter is switched off and
the receiver on for 16 minutes.

The 38.25-Mc transmitting fre-
quency is switched up or down 8 Ke
every 8 seconds to distinguish
echoes from cosmic and sun-gener-
ated noise.

Circuit Permits Accurate
Voltage Ratio Measurement
By P. A. LENK,

Reactor Control Labs,
General Dynamics/Electronics,
Rochester, N. Y

ACCURATE measurement of the ratio
of two voltages is provided by a
simple circuit using readily avail-
able parts. Its resolution is better
than 0.1 percent.

The ratio of two voltages must
often be measured accurately. For
example, it may be necessary to
measure an output voltage as a
function of a maximum level or to
determine linearity in terms of the
ratio of input to output voltage.

The circuit in the figure was de-
veloped specifically to measure the
ratio of two in-phase a-c voltages of
about 80 volts rms to within 0.1
percent. Potentiometer R, is a ten-
turn potentiometer with a ten-turn
dial. The diode provides the indica-
tion of the ratio between the un-
known voltage and a reference volt-
age. In this case, a value of 5,000

electronics

UNKNOWN
VOLTAGE

Voltmeter becomes accurate null de-
tector when difference voltage is
less than one half volt

ohms was suitable for R,.

A 115-volt, 6-watt incandescent
lamp limits voltage applied to the
voltmeter when the difference be-
tween the unknown and reference
voltages exceeds 0.5 volt. Both R,
and the lamp must be selected for
the particular application, includ-
ing the maximum power they will
be required to dissipate.

The value of R, is chosen so that
a full-scale deflection is obtained on
the meter when the difference be-
tween the two voltages is maximum.
Thus if the reference voltage were
zero, full-scale meter voltage would
be equal to the maximum value of
the unknown voltage.

Circuit Operating Principles

In operation, diodes D, and D
conduct when the difference be-
tween the unknown and reference
voltages exceeds 0.5 volt, and the
meter is shunted by R,. Also, high
voltage difference heats the lamp,
which further reduces the voltage
applied to the meter. The two volt-
ages are balanced by rotating the
potentiometer in a direction that
reduces the meter deflection.

When the difference between the
unknown and reference voltages is
less than 0.5 volt, the resistance of
the lamp becomes negligible and the
two diodes do not conduct. The dif-
ference voltage is now applied to
the meter with no appreciable se-
ries or shunt impedance so that the
3-volt meter becomes a _ sensitive
null detector. At null, the ratio of
the two voltages is indicated on the
dial of the potentiometer.

The circuit has proved to be use-
ful, particularly since it can be as-
sembled from parts readily avail-
able in most laboratories. Accuracy
has not yet been fully determined.
Resolution is better than 0.1 per-
cent, which is the smallest incre-
ment of adjustment provided on
the potentiometer.

December 29, 1961

GUARANTEE
of Quality
This GUDEBROD Lacing
Tape is Manufactured
under strict Quality
Control. Complete test
data is on file for your
protection under
Lot #18861

THIS SEAL GUARANTEES YOU
REAL LACING ECONOMY oo.

increased production

with fewer rejects !
Ts LE

Always specify Gudebrod whether you use one spool of lacing tape or thousands
because Gudebrod lacing tape is produced under strict quality control. Gudebrod
checks and rechecks every lot of tape to insure that it meets the highest standards
. .. higher standards than those required to meet MIL-T specifications.

Gudebrod helps increase your production because we carefully test, measure and
maintain close tolerances on such characteristics as slip resistance, fray resistance,
breaking strength, wax content, fungistatic effectiveness. These and other tests assure
you that when Gudebrod lacing tape is used production increases. Knots don’t slip . . .
harnesses stay tied . . . assemblies remain firm . . . there are fewer rejects!

Whatever your lacing needs—Teflon*, dacron{, glass, nylon, high temperatures,
special finishes—Gudebrod makes it or will produce a tape to meet your special re-
quirements. If you want a tape to meet 1500°F . . . Gudebrod Experimental Research
Project 173 is the answer. If you want a tape that meets MIL-T-713A . . . Gudelace®
(Style 18 Natural) is the answer.

MAKE THE H-R TEST! Write for samples of Gudelace or other Gudebrod
lacing tapes and have them tested in your harness room. Compare a harness tied with
a “Quality Controlled” Gudebrod tape and any other tape. This test will convince you
that when you specify Gudebrod you specify real economy—increased production
with fewer rejects.

Write for our free Technical Products Data Book. It ex-

plains Gudelace and other Gudebrod lacing tapes in detail.

*Dupont’s TFE fluorocarbon fiber. tDupont’s polyester fiber.

GUDEBROD BROS. SILK CO., INC.

Electronics Division Executive Offices

225 West 34th Street 12 South 12th Street
New York 1, New York Philadelphia 7, Pa.

CIRCLE 57 ON READER SERVICE CARD 57

COMPONENTS AND MATERIALS

Devices Featured At Japanese Forum

By CHARLES L. COHEN,

McGraw-Hill World News

TOoKYO—Interest here in small de-
vices—crystal resonators, capaci-
tors, resistors, photocells, magnetic
materials, varactor diodes, and in-
dicators for transistor circuits—
was evidenced by more than 1,000
Japanese engineers who showed up
to spot useful components for cir-
cuit design at the recent three-day
meeting of the Japanese Institute
of Electrical Communications En-
.gineers.
Crystal Resonator Wafers

At one of these sessions, Atsushi
Tachibana of Hibachi described the
construction of quartz crystal
resonators on 8 mm sq AI.O. micro-
module wafers. Space occupied by
the terminals leaves only 6 mm sq
space available for mounting crys-
tal. Total height from bottom of
wafer to top of metal crystal cover

is only 2 mm. Crystal resonators
measure 4.3 x 4.3 mm, resonance
frequency is 45 Mc, resonance re-
sistance is 20 to 40 ohms.

Another small component seen
was the silicon oxide dielectric ca-
pacitor, developed by Tsuyoshi
Matsunaga of Nippon Electrical
Co. The dielectric of this device
is Si,O., rather than SiO and SiO,
previously reported in Japan.

To construct this capacitor, an
aluminum electrode is first evapo-
rated on 10-mm-sq glass substrate
in vacuum. Si.O, is evaporated at a
pressure of 1 10° mm mercury,
and then a second aluminum elec-
trode is evaporated. Entire capaci-
tor is baked after lead connections
are made with silver paste.

Area of dielectric between elec-
trodes is 0.25 sq cm, capacitance is
250 pf. Insulation resistance at 20
v d-c is greater than 2 10° meg-
ohms, tan 6 at 1 Kc is better than

Heat Blanket for Accelerometers

A MOLDABLE, uncured silicone rub-
ber and glass fabric with an alu-
minum one side is
helping to solve heat applications
problems in several missile com-
ponents at Thermal Systems, Inc,
formerly Electro-Flex Corp., Gar-
dena, Calif.

In an application on the Minute-
man missile, a heater made from
the silicone based material, Irving-
ton brand SRGA fabric 0208, ( Min-
nesota Mining and Manufacturing
Co.), is used to maintain a constant
temperature inside a black box in
the autonetics system.

By using SRGA fabric to control
environment for two accelerometers
inside the box, designers of the
heating assembly were able to hold
down the weight of the heat blan-
ket, reduce the wattage require-
ments, conserving the limited power
available in the missile, and reduce
the insulation necessary to stabilize
temperatures within the box.

coating on

Typical shapes of heaters for mis-
sile electronic components made by
Thermal Systems, Inc.

These fabrics are made of spe-
cially woven and treated glass base
cloth, coated with silicone rubber
and a micro-thin facing of vapor
coated aluminum which imparts a
closely knit surface of highly-re-
flective particles. Fabrics retain
flexibility, drape and heat resist-
ance characteristic of silicon rub-
ber-coated cloths.

5 x 10“. Temperature coefficient
between —40 and 85 C is 50 x 10°
per deg C, capacitance change due
to temperature cycling is less than
0.02 per cent. However at fre-
quencies above 1 Mc capacitance
increases slightly.

Resistors and Thermistors

Tadtsugi Ito, of Waseda Uni-
versity, explained the theory of a
potentiometer with no sliding con-
tact. The gap between the parallel
or concentric resistance element
and the metal pickup element is
bridged with CdS. Point of contact
is moved by changing the position
of a beam of light. Problems still
remaining to be solved for practical
use are reduction of the resistance
of the CdS, which is too high for
low-resistance potentiometers, and
lowering of the CdS lifetime for
fast response.

Precise reproducible thermistors
were fabricated by Tomojiro
Asaba, of Tokyo Institute of Tech-
nology, from 35 to 45 ohm-cm ger-
manium. Chemical etching after
fabrication allows precise resist-

_ ance values to be obtained.

Also small are the silicon photo-
voltaic cells for card reading in
electronic computers, introduced by
Hiroyuki Nishimi of Fuji Com-
munications Apparatus Co. Major
advantage of units in pilot produc-
tion, which consist of two rows of
nine cells each on the same silicon
wafer, is ability to self-check. One
row is used for reading, while the
second row is used for checking.

Construction is similar to solar
batteries. Boron is diffused into a
25 mm diameter wafer of 0.1 to 1
ohms silicon; then grooves are
etched to separate individual func-
tional devices on same wafer. Cells
on wafer may be in rows, or in mul-
tiple rows. Negative electrode is
common, leads are attached to in-
dividual positive electrodes. Effec-
tive area of devices built to date is
1 to 25 sq cm.

Other advantages include small
size, self-generating voltage which
eliminates the need for bias sup-

electronics

“electronics

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R-5 Electronic Markets Special Report 3
R-7 Electronics Research and Development Around the World
R-17 1960-61 electronics Buyers’ Guide Reference Section 64
Medical Electronics—
R-19a Part |: Diagnostic Measurements
R-19b Part Il: Diagnostic Systems and Visualization €
R-19¢ Part Ill: Therapeutic Devices
R-19d Part IV: Prosthetics—Hearing Aids and Blind Guidance Devices
R-19¢ Part V: Prosthetics—Substitute Organs and Limbs
R-19f Part VI: Observing Life Processes
R-21 Electronics in Europe
Plasma Engineering
R-22a Part |: Generating and Heating F ma
R-22b Part Il: Measuring Parameters
R-22 Part Ill: Practical Applications of Plasma
R-23 What's New In Semiconductors
R.24 Reference Section 1961-62 electronics Buyers’ Guide
R-25 1961-62 electronics Buyers’ Guide Product Listings
Manufacturers Index
Lasers: Devices & Systems
R-26a tart Principles of Functioning a ser Mate
R-26t Part I!: Communications, Navigati« Rang and
Undersea Applicat 1s
R-26¢ Part lil: Military and Computer Appi
Frequency Tuning, Modula n, Demodula Mixing Techniques
R-26d Part IV: Scientific and Medical Apr t aser Optics
Commercial! Equipment :
. 5
R-27 Missile And Space Electronics
) e ¢ € ¢ ea f ¢ ea

a .
ft

plies, fast response, spectral char-
acteristics similar to the human
eye, insensitivity to temperature
changes, and long life. Output cur-
rent is approximately 50 »A/mm*
for light source of 3,200 K, 10,000
lux; under these conditions output
voltage is approximately 0.45 volts.

Also for computers is a method
of using commercially available 1.2
mm ferrite cores in memories
which feature non-destructive read-
ing. This development, reported by
Hiroji Ihara of Nippon Electric
Co., makes use of reset, writing and
symmetrical reading pulses.

Yukio Fukukawa, of Fuji Com-
munication Apparatus Co., intro-
duced a small three-electrode neon
bulb indicator which operates with
a small voltage change on its con-
trol element. This tube is espe-
cially useful as an indicator in
transistorized computers and
counters. Concept applied is remi-
niscent of the Philips decade indi-
cator (see ELECTRONICS, Nov. 3, p
60).

Varactor Diode Application

Akio Sasaki, of Kobe Kogyo, de-
veloped a new method of controlling
the frequency of reflex klystrons.
The change of capacity of reversed
biased varactor diodes was used to
change the resonant frequency.
Microwave Associate’s MA 4600
diodes were used in this experi-
ment. With the diodes located in
the cavity outside of the evacuated
portion of the 7V204 reflex klys-
tron, approximately 2.5 to 10 Me
variation could be obtained at 7,000
Me.

It would be desirable to vary
both repeller and diode voltage
simultaneously to realize the fol-
lowing conditions;
ductance G,
ance G

electron con-

plus circuit conduct-
equal zero. Electric
susceptance B. plus circuit suscept-
ance B.. equal zero. Then output fre-
quency could be varied over a rela-
tively wide frequency band with
almost constant power output. This
would enable FM signals with small
AM component and low differential
modulation distortion to be ob-
tained.

Several means of eliminating in-
terference to X-band radar from
rain and snow were explained by
Noriomi Ochiai, of Tokyo Keiki
Seizocho KK, in the symposium on

December 29, 1961

Aeronautical and Marine Radar.
Cireularly polarized radiations
were used. The metal grid circular-
izer was developed for marine
radars, which customarily use
horn-fed reflector antennas. Ochiai
showed a comparison of ppi radar
patterns made using horizontal
polarization and those made using
circular polarization. A buoy
clearly visible through heavy rain
when using circular polarization
was completely masked when using
horizontal polarization.

Indium Antimonide Used As
Voltage Regulator Element

OUTPUT VOLTAGE of this magneto-
resistance voltage regulator is kept
constant by an indium-antimonide
semiconductor, measuring } by }
by 0.004 inch, whose resistance
varies in proportion to the strength
of an applied field.

Designed specifically as a supply
source for a tunnel diode, this de-
vice is one of the first practical
units to use the phenomenon of
magnetoresistance. An increase in
input produces a stronger field in
the electromagnet (coiled wire in
the photo), thereby increasing the
resistance of the indium-antimonide
element.

The regulator can maintain a
0.15-volt output within +5 per cent
at 0.1 amp, even when load resist-
ance changes 50 per cent with a
simultaneous 10 per cent change
in input voltage, which is normally
1.5 volts. Much more precise regu-
lation than this can be achieved
when magnetoresistance is used in
regulators with outputs of one volt
or more.

The regulator was developed by
3attelle Memorial Institute, Colum-
bus, Ohio, as part of a program to
determine the feasibility of em-
ploying indium-antimonide in elec-
tronic devices.

newest,
simplest way
to measure
r-f power...

PRD 680
calorimetric
power meter!

., With this new instrument you
can measure power accurately

and directly, from a few micro-
watts up to a half watt. No bolometers,
barretters, thermistors, or external atten-
uators are necessary. Nine power ranges
can be selected on the front panel dial,
and direct power reading in DB or watts
can be made in seconds. Instrumentation
is accurate to 2%. A lightweight (20
lbs.) , easily portable unit, the PRD 680
utilizes the PRD series of dry calori-
meters which plug into the front panel
interchangeably. Shown here is the
N680, covering the range of 0 to 10
kme/sec. Waveguide plug-in units for X
and K bands will be available soon.

Send for data!

PRD ELECTRONICS, INC.

202 Tillary St., Brooklyn 1, New York
ULster 2-6800

1608 Centinela Ave., Inglewood. Calif.
ORegon 8-9048 ,
A Subsidiary of

Harris-Intertype Corporation overs

HARRIS

INTERTYPE
. onsen

CIRCLE 61 ON READER SERVICE CARD 61

PRODUCTION TECHNIQUES

Clock Motor

Speeds Servo
Motor Tests

By THOMAS POTTS
Servo Dynamics Corp.
Somersworth, N. H.

MANY SERVO MOTORS in use today
have never met the starting voltage
requirement they were designed
and tested for, due to the inade-
quacy of the methods and test pro-
cedures used to measure starting
voltage. Over the past few years
many different methods of measur-
ing the starting voltage of a servo
motor have been tried," * * * *° but all
give values that are inconsistent
and unrepeatable; usually the test
must be repeated several times and
the poorest result used as the best
approximation. Even after tests
have been run many times, it is still
possible that the poorest value for
a particular unit has not been
found’.

Plots of starting voltage versus
the initial position of the shaft may,
under some conditions on some
units, vary as much as five to one.
In addition, clockwise and counter-
clockwise tests (Fig. 1) shows that

Servo

62

motor test set-up showing special fixture for
motor and related measuring equipment

ROTOR POSITION O

IN DEGREES

FIG. 1—Plots of starting voltage for cw and cew rotation. Rotor slots create
localized effects where starting voltage essentially goes to zero

variations in maximum and mini-
mum values 77 starting voltage are
not necessarily the same for both
directions of rotation. This is
caused by magnetic and electrical
anomalies, not bearing friction as
is generally supposed.

To insure that a servo motor will
always start in a system at rated
starting voltage, the testing method
should meet several requirements:

it should be practical for production
testing, find all the points of high
starting voltage for both directions
of rotation, be easily and quickly
accomplished with a minimum of
extra equipment, and be repeatable
from day to day and be independent
of test operator judgment.

In actual system use, servo mo-
tors are almost never run no-load.
In most systems either a tachom-

FIXED
p— PHASE
VOLTAGE

RE-
VERSIBLE
Sw

SPEC.
STARTING

COUPLING SWITCH VOLTAGE

FIG. 2—Clock motor is enough load on the servo motor
to stop it if starting torque is below specs

electronics

R7NC “HEAVY DUTY”

BY-PASS DISCAPS,

SPECIFICATIONS
POWER FACTOR: 1.5% Max. @ 1 KC
weer: Type B DISCAPS meet or exceed all EIA
POWER FACTOR: 2.5% Max. @ 1 KC RS-198 specifications for Z5U ceramic capaci-
(after humidity) 7 ,
tors. Designed for by-passing, coupling, or
WORKING VOLTAGE: 1000 V.D.C. filtering applications, Type B DISCAPS are
TEST VOLTAGE (FLASH): 2000 V.D.C. manufactured in capacities between .00015
and .04 MFD.
A heavy ceramic dielectric element provides
INSULATION: Durez phenolic—vacuum a safety factor where steady or intermittent
waxed high voltages occur. Type B DISCAPS show a
INITIAL LEAKAGE RESISTANCE: Guoran- minimum capacity charge between +10°C and
teed higher than 7500 megohms +85°C (see curve).
AFTER HUMIDITY LEAKAGE RESISTANCE:

Guaranteed higher than 1000 meg-
ohms

LEADS: No. 22 tinned copper (.026 dia.)

TYPICAL =
CAPACITY VS. TEMPERATURE
TYPE-B-DISCAPS
25° TO 85°C

25°C VALUE

PERCENT CHANGE

FROM

TEMPERATURE °C

DISCAP RADIO MATERIALS COMPANY

CERAMIC A DIVISION OF P. R. MALLORY & CO., INC.
CAPACITORS \ GENERAL OFFICE: 4242 W. Bryn Mawr Ave., Chicago 46, III.
>, Two RMC Plants Devoted Exclusively te Ceramic Capacitors

= weil

CIRCLE 63 ON READER SERVICE CARD 63

December 29,

MAKING ROOM AT THE TOP

omaeeamreeonererman tea Nt SOARES “OR hs ane SNARES REGRET MORBONRE HERETO

4 S F
> teetbeod,,, e
.** eehere -. ——
oe us "bore,

x oe

See the 41 additional EICO instruments help-
ful for your lab and line work. Write for free
catalog and name of neighborhood distributor,

@ Dept. E-12¢
3300 N. Bivd., L.1.C. 1, N.Y.
cpg Export Dept.: Roburn Agencies, Inc.
431 Greenwich St., N. Y. 13, N.Y.

Add 5% in the West.

EICO creates a new,
professional lab quality
test instrument series

at moderate prices.

AC VTVM &
AMPLIFIER

#250
Kit $49.95, Wired $79.95

VTVM: 12 ranges from imv to 300v

response absolutely flat from
10 cps to 600 kc; input impedance
10M shunted by 15uyzf; accuracy
+3% of full scale.

Note: Average responding meter
calibrated in rms. Linear 0-1, 0-3
scales. Decibel scales based on
Odb=1mw in 600{2 with 10db in-
terval between ranges.

AMPLIFIER: 60db gain on Imv range;
response +0, —3db from 8cps to
800kc; output to 5V rms undistorted,
variable down to zero by attenuator
contro! at output; input impedance
10M22, output impedance 5K2; hum
: noise —40db for signal inputs above
mv.

DESIGN QUALITY: All frame-grid
tubes; 60db frequency-compensated
input attenuator ahead of cathode
follower with 10db/step attenuator
following; two-stage R-C coupled am-
plifier and full-bridge meter circuit in
one overall feedback loop; no response
adjustment required in amplifier cir-
cuit; single sensitivity adjustment;
voitage-regulated power supply. 50/60
cycle operation.

EICO MODEL 255 AC VTVM
identical to Model 250 described
above, but less amplifier facility. 50/60
cycle operation.

Kit $44.95 Wired $72.95

64

CIRCLE 201 ON READER SERVICE CARD

The high standards of MITSUMI electronic

components are insured by a fully-auto-
mated assembly system, and double-checked
by rigid quality controls. Mitsumi Electric
Company is Japan's largest manufacturer
of components for radio, television and

communicetions equipment.

Good
parts
work
best!

Intermediate
Frequency
Transformer
\FT

MITSUMI PARTS

MITSUMI ELECTRIC CO., LTD.

Komae, Kitatama, Tokyo

CIRCLE 64 ON READER SERVICE CARD

POLYVARICON
Variable
Copacitor

eter, synchro, gear train, indicator,
etc., presents some small load to the
motor. Further, tests indicate that
under conditions of a small load, the
variations in maximum and mini-
mum starting voltages increases.
Thus there are larger discrepancies
in the characteristics of a motor in
a system than are predictable from
normal methods of measuring start-
ing voltage. To meet all of the
above requirements, Servo Dynam-
ics Corp. developed a method for
testing each motor for all positions
of the rotor in both directions of ro-
tation, under conditions of a very
light load. This test, shown in Fig.
2, is simple, quick, eliminates oper-
ator judgment, and gives repeat-
able results in production.

The reversible drive motor is a
low speed clock motor connected to
run so that the drive half of the

As long as the two halves of the
coupling remain in contact, servo
motor meets starting voltage specs

coupling linkage moves in the same
direction as the motor under test.
Thus the linkage acts as a brake or
load on the motor being tested. Dur-
ing the test the servo motor is ener-
gized with normal fixed phase volt-
age and with specified maximum
starting voltage on the control
phase. The reversible drive motor
is then run and the operator ob-
serves whether or not the two
halves of the coupling linkage re-
main touching at all times during
one complete rotation of the motor
output shaft. The phase of the con-
trol voltage is then reversed and
the drive motor is reversed. The
test is then re-run, again observing
whether or not the two halves of the
coupling linkage remain touching
for one revolution. If the servo
motor stops, allowing the two halves
of the coupling linkage to separate,
then the starting voltage of the
servo motor exceeds the specified
maximum. The test has bee: vua'-

electronics

uable for production testing since
it is a uniform and reproducible
method that is wholly determined
by the motor itself and is independ-
ent of the skill or judgment of the
test operator.

To find the actual maximum or
minimum starting voltage of a mo-
tor, the voltage on the control phase
can be adjusted until the motor
under test just rotates for both di-
rections of test without permitting
the linkage halves to separate. To
eliminate marginal units, all motors
can be tested at 95 percent of speci-
fied starting voltage.

REFERENCES

(1) ARP-497, “Aeronautical Recom-
mended Practice-Precision Control Mo-

ors”, SAE.

4 ARP-667, “Aeronautical Recom-
Practice- Pre ‘ision Motor Tach-
eter Generator’, SAE
MIL-S- 17087, “Servo Motors-2
Phase, 400 Cycle”

(4) MIL-S-17 806, (NOrd), “Servo Mo-
tor-T ache ymeter Generator, 2 Phase, 400
Cycle’

(5) MIL-S-22432 (WEP), “Servo Mo-
tors-General Specification”.

(6) Bureau of Naval Weapons, “Study
of Standardization of Servo Motor and
Tachometer Generator Acceptance Test
Equipment,” June 1960. Contract N164-
8637 of Lockheed Electronics.

Silicon Rectifiers
Directly Soldered

A DIRECT soldering technique has
been developed for manufacturing
silicon power rectifiers. The method
uses a diffused silicon junction to
which copper disks are soldered;
molybdenum or tungsten washers
are not required. Cells with current
ratings to 400 amps, and with peak
inverse voltage ratings from 1,000
to 1,200, can be produced.

The technique is based on the
stress, strain and thermal expan-
sion characteristics of silicon and
copper. Calculations show, and ex-
periments confirm, that if ¢./D is
approximately 0.2 or _ greater
(where t. is the thickness of the
copper electrodes and D the diam-
eter), and if t,/D is approximately
0.02 or less (where t¢, is the thick-
ness of the silicon disk and D its
diameter), thermal stresses will not
be strong enough to cause rectifier
failure during normal operatio..
The two copper disks are the same
diameter as the silicon disk and are
the outer layers of the rectifier
sandwich.

Otomi Fujii describes the process
in the Summer 1961 issue of
Toshiba Review.

December 29, 1961

JUST WHAT THE DOCTOR ORDERED

7 regen

LOW NOISE FIGURE

12 MILLIAMPERE POWER DRAIN
flashlight

SMALL SIZE— Lisi WEIGHT
21" x a

THE NEMS- CLARKE

‘SOLID STATE TELEMETRY PREAMPLIFIER

| SOLID STATE PREAMPLIFIER |

a

Here’s your baby for outstanding performance and economy
in the 225-260 megacycle telemetry range —the Nems Clarke
SSP-101 completely solid state preamplifier. Featuring
extremely low noise, flat response, and a hefty 25db minimum
gain, it’s at home in any environment... installed either in
the antenna mount or the coax cable. Its own external 12 volt
power supply is available for rack mounting. Baby sitting?
Forget it! The SSP-101 operates for thousands of trouble free
hours at unattended locations.

Write for Data Sheet 999

ee

PRODUCERS OF NEMS-CLAREE EQUIPMENT

| 919 JESUP-BLAIR DRIVE, SILVER SPRING, MARYLAND / 2301 PONTIUS AVENUE, LOS ANGELES 64, CALIFORNIA

CIRCLE 65 ON READER SERVICE CARD 65

New On The Market

Memory Systems
COINCIDENT CURRENT

DAYSTROM, INC., Archbald, Pa.
Military derived ceincident current
memecry systems offering cycle
times to 3.5 psec are available at
commercial prices. The CCM series
is available in random access, se-
quential-interlaced and sequential-
non-interlaced models. Design per-
mits modular construction and

Tape Storage Unit
MILE-A-MINUTE

INTERNATIONAL TELEPHONE AND
TELEGRAPH CORP., 320 Park Ave.,
New York 22, N.Y. The ITT British
associate, Creed & Co. Ltd., has in-
troduced a tape storage unit that
provides automatic retrieval and
read-out of prepunched tape data on
reels revolving at speeds of 60 mph.
Mode! 2000 has a capacity of 240,-
000 alphanumeric characters per
reel. Maximum access time is 13
sec.

CIRCLE 302 ON READER SERVICE CARD

Transponders
SMALL AND LIGHT

A£RO GEO ASTRO CORP., 1200 Duke
St., Alexandria, Va. The AGA S/T-

66

facilitates incorporation of the unit
in a wide variety of data handling
systems. A _ variety of memory
capacities are available with word
sizes to 4096 and bit lengths to 64.
Capable of operating with a tem-
perature range of 10 C to 35C.

CIRCLE 301 ON READER SERVICE CARD

CV and AGA C/T-CV transponders
weigh slightly more than 5 lb each.
These units, designed for use in
missiles and drone targets, increase
the volume of radar signals from
the missiles or drones, thus aiding
ground stations in tracking and
other operations.

CIRCLE 303 ON READER SERVICE CARD

Stepping Switch

UNIFORM RATCHET WEAR
DAVIS. RELAYS LTD., P.O. Box 549,
Times Square Station, New York
36, N.Y. Stepping switches give
250 million operational steps in ac-
celerated life tests; hence a stepper

with 5 bands of 50 contacts and
costing $24.70 scans a million in-
puts for just under two cents. Stag-
gered wiper-and-brush springs pro-
vide uniform ratchet wear and
smoother stepping. Electrical cun-
tacts are rated at 3 amp when the
stepper is at rest and 1 amp when
the rotor is turning. Stepper has
application in systems that require
a programmed sequence of opera-
tions.

CIRCLE 304 ON READER SERVICE CARD

Wire-Wound Pot
FINE RESOLUTION

VOGUE INSTRUMENT CORP., 2350 Lin-
den Blvd., Brooklyn 8, N.Y. Based
on a lift slidewire design, model
181-S pot combines infinite resolu-
tion with stability of wirewound
pot. Wiper rides on a lead screw and
the wire is always in contact with
one point only on the wiper blade.
With continuous rotation and life,
the unit develops lower noise. Re-
sistance ranges: from 2 to 750
ohms per turn, with a max of 40
turns available. Linearity can be
maintained to 0.01 percent.

CIRCLE 305 ON READER SERVICE CARD

Pulse Generator
FOR INDUSTRIAL USE

RELIANCE ELECTRIC AND ENGINEER-
ING CO., Cleveland 17, O. Pulse gen-

electronics

oF

THE SIZE DIMINISHES; Kd THE POWER REMAINS AS HIGH

Tiny New 3/8” (0.375’) Squaretrim®
Potentiometer Dissipates One Full
Watt In Still Air!

eeeeevene

The performance of this new Daystrom subminiature Squaretrim is as great as its half-inch cousins. Further,
the one-watt rating is based on still-air tests...typical of our conservative specifications. Contained in a stack-
able package only °s” square and just %” thick, the new Series 200 Squaretrims permit great circuit density
(27 per cubic inch) and the 144 different models offered give wide design latitude. The Series 200 Squaretrims
range from 10 ohms to 35K, operate from —55 to +150°C, and need no mounting brackets for stacking. A true
precision instrument with all the exclusive features of the Daystrom line, this new potentiometer is designed
to meet MIL R-27208 and MIL R-22097. Write for detailed information.

FRA,

DAYSTROM., incorRPORATED

eet” ;
POTENTIOMETER DIVISION

ARCHBALD, PENNSYLVANIA « LOS ANGELES, CALIFORNIA

December 29, 1961 CIRCLE 67 ON READER SERVICE CARD

MINIATURE RESONANT REED SELECTORS

These miniaturized selectors are useful in multiplex telemetry, mobile
communications, and other applications where space and weight are at
a premium. Their secret is a new electro-mechanical driving system that
allows both the reed and driving coil to be sealed in a case only 36mm
long and 12.6mm in diameter. Each selector will respond to one of 40
audio frequencies spaced at 15 cps intervals from 262.5 to 847.5 cps,
and actuate signals, counters, controls or other devices. Normal drive
current is 25ma. Selectivity is +1.5 cps from calibrated frequency, and
Stability is within +0.5 cps of calibrated frequency from —10 to +50°C.
Detailed specifications and application information are available from

our representatives listed below.

(G) FUJI TSUSHINKI SEIZO OE silicic

Represented by:

M@ The Nissho American Corporation () New York 5, 80 Pine St., WH 3-7840 DJ Chicago
3, 140 S. Dearborn St., CE 6-1950 § The Nissho Pacific Corporation () San Francisco
4, 120 Montgomery St., YU 2-7901 [J Los Angeles 14, 649 S. Olive St., MA 7-7691

CIRCLE 68 ON READER SERVICE CARD

NEW IDEAS FOR SALE!

Words and pictures tell you about the top
new product ideas each week in “On the
Market’. Who makes ’em and what they’ll
do for you. Easy way to keep in touch with
the latest and best.
Another reason why it will pay you to
subscribe to electronics (or renew your sub-
FIND WHAT _ scription) right now. Fill in the box on

Reader Service Card. Easy to use. Postage
YOU NEED IN... free.

electronics

erator is designed for industrial
digital control systems. Device is a
quantizer that provides a digital
output that is a function of the
speed or accumulated rotary posi-
tion of its input shaft. It is con-
structed to withstand the normal
abuse of in-plant usage. It will op-
erate from zero speed up to 4,000
rpm and accurately generate a
maximum of 15,000 pps. Each pulse
is a 15 v square wave at all speeds,
with a minimum duration, at top
speed, of 25 psec.

CIRCLE 306 ON READER SERVICE CARD

Controlled Rectifiers
UP TO 600 VOLTS

SEMICON, INC., 200 Sweetwater
Ave., Bedford, Mass. These semi-
conductor triode switches are de-
signed for use ‘in power control and
high current switching applications
requiring blocking voltages up to
600 v. Units are applicable for load
currents up to 5 amp. Long leakage
path eliminates voltage breakdown
between terminal and case. A triple
diffused silicon pellet makes for
maximum uniformity and reliabil-
ity. Units exceed MIL-E-1 and
MIL-S-19500B.

CIRCLE 307 ON READER SERVICE CARD

High-Speed Electrolytes
SELECTIVE PLATING

SELECTRONS, LTD., 153 E. 26th St.,
New York 10, N. Y., announces
high-speed selective electroplating
solutions, intended for use with the
company’s table-top electroplating
systems. By means of special sty-
luses and power- packs, controllable
amounts of alloys, as well as metals,
are deposited on selected areas
without having to immerse the
entire object in electrolyte.

CIRCLE 308 ON READER SERVICE CARD

electronics

“The light touch. . .
in automation and control”

: re

CLAIREX
Mod tel rolaelate (lia tele

=

LA

Ser ‘

Illustrated;
an “L” type
particularly
useful in
tae latiitiels
relate Meh tal-1g
low-voltage
applica-
tions,

from the
aalialiohitia-)
600 series.

A

Circuit
Component
Controlled by
LIGHT

For tabulated technical
dete on 25 different
Cloirex Photoconductors
consult your new

* IRE Directory

* Electronic Buyers
Guide

® Electronic Design
Catalog

* Radio Electronic
Master

CLAIREX

ele) ite) 7-Wilel.

19 W. 26 St., New York 10, N. Y.
MU 4-0940

CIRCLE 202 ON READER SERVICE CARD
December 29, 1961

Literature
of the Week

IR TEST INSTRUMENTATION _Infra-
red Industries, Inc., Box 989, Santa
Barbara, Calif.A brochure describes
a line of laboratory and production
test equipment for infrared compo-
nents and systems. (309)

SERVO ACCELEROMETER Gulton In-
dustries, Inc., 212 Durham Ave.,
Metuchen, N.J. A technical bulletin
describes and illustrates Glennite
unidirectional, biaxial and triaxial
servo accelerometers. (310)

TRANSDUCER POWER SUPPLY & BAL-
ANCE Microdot Inc., 220 Pasadena
Ave., South Pasadena, Calif. Data
sheet PB-1 describes transducer
power supply and balance units,
models PB-290 and PS-290. (311)

STATIC RELAY Airborne Acces-
sories Corp., 1414 Chestnut Ave.,
Hillside 5, N.J. Bulletin PS-9 de-
scribes the ult-Relay, an ultrasensi-
tive static relay. (312)

HEAT SINKS Astro Dynamics,
Inc., Second Ave., Northwest Indus-
trial Park, Burlington, Mass., has
prepared a manual for rapid selec-
tion of the proper heat sink to meet
specific conditions. (313)

VOLTMETERS Trio Laboratories,
Inc., Dupont St., Plainview, L.I.,
N.Y. Engineering bulletin catalogs
a complete line of single and multi-
range a-c and d-c vacuum-tube and
transistorized voltmeters. (314)

R-F CONVERTERS Centimeg Elec-
tronics, 312 E. Imperial Highway,
El Segundo, Calif. R-F amplifiers
and converters are described in
data sheet 1161. (315)

COMPUTER ELEMENTS Ransom Re-
search, 374 W. Eighth St., San
Pedro, Calif. Catalog C covers a line
of printed-circuit, solid-state com-
puter elements. (316)

MICROWAVE DEVICES Microwave
Technology Inc., 235 High St., Wal-
tham 54, Mass. A four-page short
form catalog describes over 75 ad-
vanced microwave devices. (317)

TEST LEADS & COAX CABLES Angler
Industries, Inc., 75 Winthrop St.,
Newark 4, N.J. Four-page catalog
constitutes a handy quick ordering
guide to a full line of test leads and
coaxial cables. (318)

| VY, tibel

TO SAVE YOU MONEY

PANEL MOUNTING
ALL-ANGLE BLOWERS

One multi-purpose model in stock
will eliminate procurement of
several single-purpose units to
satisfy variable requirements.
Large cooling capacity.

Twin scrolls can

be rotated and set

to angle of choice through 230°
for accurate air flow control.

Use for supply or exhaust—or one
port for supply, the other exhaust.

__.

MODEL AAB — 834

Mount as standard 854", 7” or
312’ panels. Blower unit of 34”
model is recessed to allow extra
usable chassis or storage space.

MODEL AAB — 31/2

=
@ MIL quality heavy duty construc-

tion and finish or finish to Customer
specs ® Easy maintenance without
removal from cabinet @ Cushion
mounted for quiet operation

@ Cleanable filter e Motor bearings
permanently lubricated

Ask for complete data — our Bulletin D-1000
ONE SOURCE...

for VENTILATED RELAY RACK CABINETS,
CONTROL CONSOLES, BLOWERS, CHASSIS,
CHASSIS-TRAK, RELATED COMPONENTS

ORegon 8-7827

Western Devices, Inc.

600 W. FLORENCE AVE., INGLEWOOD 1, CALIF.

CIRCLE 69 ON READER SERVICE CARD 69

PEOPLE AND PLANTS

Filtors Erecting Space Age Plant

FILTORS, INC., Huntington, L.I.,
N.Y., recently broke ground for
eonstruction of what its officials
termed “the factory of the future.”
When completed next fall, the plant
will produce hermetically sealed
subminiature and microminiature
relays on an automated production

line in controlled atmosphere un-—

der ultraclean conditions.

The company also recently an-
nounced a research program to de-
velop a “second generation of super-
reliable relays” to be produced in
the new plant.

Filtors’ new facility will occupy
62,900 sq ft on 22 acres in the
Township of Huntington, about 40
miles from downtown Manhattan.
The single-story structure will have
double walls of concrete blocks sepa-
rated by a 4-in. air pocket. The pro-
duction area, totalling 37,900 ft,
will be windowless and be equipped

Micro Link Acquires
Additional Space

FURTHER expansion of the activities
of the Micro Link Corp. has necessi-
tated the leasing of additional space
at 1355 Marconi Blvd., Copiague,
inte

The Micro Link Corp., a wholly
owned subsidiary of LEL Inc., is
engaged in the development and
manufacture of low cost point-to-
point microwave links for use on

70

with a 220-ton air conditioner, a
humidity-control system that will
maintain a relative humidity of 50
percent, and an electrostatic dust
filtering system. In addition, 1,600
sq ft have been set aside within the
production area for a “white room.”

In this room, which has extra
atmosphere control, technicians

garbed in lint-free clothing will as-
semble the new relays.

According to C. G. Barker, vice
president for sales, the new facility
will permit an annual sales volume
of over $12 million compared with
$8 million at present. The plans pro-
vide for expanding production
capability to about $20 million an-
nually.

At the present rate of pro-
duction, Filtors will employ ap-
proximately 400 people and bring
an annual payroll of more than $2
million to the Suffolk County area.

frequencies allocated to the busi-
ness radio services.

Honeywell Buys
Denver Plant

MINNEAPOLIS-HONEYWELL REGULA-
TOR CO. announced it has purchased
the Thompson Ramo Wooldridge
plant near Littleton, Colo.

James H. Binger, Honeywell
president, said the company will

use the 146,000-sq ft building as
manufacturing and engineering
headquarters for its Denver-based
division.

Currently, Honeywell’s Denver
operation employs 550 people. It
will have moved into the new loca-
tion by New Year’s Day, according
to William D. Owens, general man-
ager.

Owens also said production of
certain products previously made
by Honeywell in a leased facility at
Beltsville, Md., will be integrated
into the Denver operation. These
include high-speed magnetic tape
data recording and playback sys-
tems for industrial, military and
scientific uses.

Pietenpol Joins
‘IBM Components

WILLIAM J. PIETENPOL has joined
IBM’s Components division § in
Poughkeepsie, N. Y., as manager of
component development. He comes
to IBM from Sylvania Electric
Products, Inc., where he was vice
president and general manager of
the Semiconductor division.

From 1950 to 1958, Pietenpol was
with Bell Telephone Laboratories,
serving as director of development,
semiconductor devices, for three
years.

Bart Manufacturing

Appoints Marvin
APPOINTMENT of Albert A. Marvin,
formerly with Amphenol-Borg Co.,
to the post of manufacturing man-
ager for the Bart Mfg. Corp. and
its subsidiary, F. C. Kent, Inc.,
both in Newark, N. J., is announced.

Bart Mfg. is engaged primarily
in the electroforming of electronic

electronics

Please clip coupon below and use right now.

WHO MAKES POWER ‘t j
TRANSISTORS LIKE
DELCO RADIO

MAKES POWER TRANSISTORS ?

nobody

You see, Delco has made more power transistors than anybody else around. We've made them
in all sizes. Diamond and round base. Industrial and military. In a wide variety of parameters. For
endless applications. With high reliability. JJ Sometime—perhaps today—you may be looking for
a transistor that’s not in our catalog . .. or any catalog. You may need samples or production
quantities. Chances are we already have it, and at a price you'll like. JJ Clip the coupon, fill in the
information and mail to our nearest office, listed below. Your inquiry will be processed immediately.

GENTLEMEN: | need a power transistor that will meet these specifications.
Collector diode voltage
Emitter diode voltage

Emitter current (continuous)

Base voltage

Saturation voltage

Thermal resistance (junction to case)

Thermal capacity for pulses in the 1 to 10 millisecond range
Collector to emitter voltage

Estimated quantity required
My name

Company

Street address

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bewcoeeeeeeeeeeesesess esses

Union, New Jersey Santa Monica, California Chicago, Illinois
324 Chestnut Street 726 Santa Monica Blvd. 5750 West 51st Street
MUrdock 7-3770 UPton 0-8807 POrtsmouth 7-3500

Detroit, Michigan Syracuse, New York Division of General Motors
57 Harper Avenue 1054 James Street Kokomo, Indiana
TRinity 3-6560 GRanite 2-2668

December 29, 1961

METALS for ELECTRONIC APPLICATION
rolled ULTRA THIN

by OUR SPECIAL ROLLING
TECHNIQUE oe

DL mr

MOLYBDENUM

5
cpECIAL pron

TOLERANCES CLOSER THAN COMMERCIAL STANDARDS
Note: for highly engineered applications—strips of TUNGSTEN
and some other metals can be supplied
celled down to .0003 thickness

@ Finish: Roll Finish—Black

@ Ribbons may be supplied in Mg. weights
Developed and Manufactured by

3229 BERGENLINE AVE. UNION CITY, NEW JERSEY
aa r ROSS @) Tele: Union City, N.J.: UN. 3-1134
e ® ® NY.C., N.Y: BR 9-4425

CIRCLE 203 ON READER SERVICE CARD

STRY) FINDS COLORADO

sRICH!
e Companies “prospecting
for plant sites”...find rich
. new benefits in Colorado.
Pleasant Living, a product
of Colorado’s magic cli-
mate attracts and holds

the most competent per-
sonnel. Industry’s west- |

ward migration has made

Colorado the transporta- :
tion hub serving the vast “di S
new markets west of the

Be arcissiPei.“Site-see”| Operational guidance for buyers
your desk, That’s what your 1961 électronics
Buyers’ Guide and Reference Issue
gives you... this year more than
ever before.
Your EBG jis bigger and better

this year than ever .. . and more |
helpful than ever .. . with more new |
exclusive features than ever. Keep
it close at hand, you'll find it’s use-

SEND FOR FREE EXECUTIVE PORTFOLIO| | ful day in and day out.
“INDUSTRIAL COLORADO.” Newly completed | |
9-booklet portfolio on Colorado’s industrial |

sites, assets, opportunities and weekend vacation electronics
wonderland. All inquiries held confidential.

; BUYERS’ GUIDE
C oO LO R és D o and Reference Issue _
DEPARTMENT OF DEVELOPMENT |

70 State Capitol Denver 2, Colorado me ound Buying Guide
in Electronics désce 7947

72 CIRCLE 72 ON READER SERVICE CARD

components and components for
missile and space applications.

Kent is a precision tube bending
concern which produces components
for aircraft and missiles and makes
waveguide forms for the electronic
industry.

American Electronics
Elects Loomis

ROBERT C. LOOMIS has been elected
president and chief executive officer
of American Electronics, Inc., Ful-
lerton, Calif., effective January 1,
1962. Prior to joining the firm, he
was president of the Convair San
Diego div. of Genera] Dynamics.

In his new post, Loomis will be
in full charge of the company’s
multi-division operations in Fuller-
ton and Culver City, Calif.

PEOPLE IN BRIEF

David D. Doran, formerly with
Daystrom, Inc., named director of
R&D for the Van Dyck Corp.
Thomas H. Miller leaves Vitro
Laboratories to join Frederick Re-
search Corp. as director of engi-
neering. Geophysics Corp. of
America promotes Richard D.
Coons to v-p and mgr. of technical
operations. Dan Cameron, ex-Lit-
ton Industries, now on technical
staff of Computer Control Co. Rob-
ert E. Shuken, previously with
ACF Industries, appointed elec-
tronic projects mgr. at Northeast-
ern Engineering, Inc. Cecil R.
Frost and Arthur S. Sheppard,
formerly with Rocketdyne and
Electronic Specialty Co., respec-
tively, hired by Canoga Elec-
tronics Corp. as senior project en-
gineers. Harrison Randolph leaves
Northern Ordnance, Inc., to be-
come v-p and g-m at Raven Indus-
tries, Inc. Wellesley J. Dodds, ex-
Bomac Laboratories, now chief
engineer of beam tubes at Met-
com, Inc. Edwin Greenstein, for-
merly with Teleprompter Corp.,
appointed v-p in charge of engi-
neering for Video Engineering Co.,
Inc. Dean Knutson, previously
with Telemeter Magnetics, Inc.,
joins Electronic Memories, Inc., as
senior applications engineer. Ro-
olfo M. Soria, v-p research and
engineering, Amphenol-Borg Elec-
tronics Corp., is elected a director
of the company.

electronics

IN STOCK FOR IMMEDIATE DELIVERY

TYPE STYLE
Right Hand
Right Hand

Left Hand

STOCK SIZES
Spirec Pivot Drills
Flat Pivot Drills
Spirec Pivot Drills
Spirec Center Drills Right Hand

Other sizes and styles available on special request.

CALL SIGN
a T
vwos wannincs NO Fe oer
(cove) EST (VOICE)
———

pocgnananse ns ¥
RADIO PROPAGATION |
FORECAST (Cove)! |
0 0 Ww M 2 30. 4

? wos
TYPICAL INTERVAL : ee wants
vont ott" icone) ®
cost) rn

RADIO
PROPAGATION
FORECAST
(cove) @

RIMARY STANDARDS

hether you want to pace a city’s clocks
br time the transit of an artificial satellite,
ou’ll find the standard time intervals and
requencies broadcast by the National Bureau
bf Standards of vital assistance.
You’ll find a complete run-down on this

BS service in your 1961 electronics
Buyers’ Guide and Reference Issue,
blus information on how you can
bbtain NBS calibration of practically any

ectronics |

' ;
secondary standard, from resistance to H

|

}

;

he complex elements of the tensor |
bermeability matrix. t |
Wealth of information like this

akes your 1961 EBG a primary
eference volume in the electronics field.

You'll find new uses for it every day.

ge agaeee BUYERS' GUIDE and Reference Issue
( The Basic Buying Guide in Electronics aéace 7947

0.04mm to 1.00mm by 0.01mm increments

0.10mm to 1.00mm by 0.01mm increments

known the world over as

the symbol of the finest in micro-drills. Insist
on them by name. Your best assurance of
quality and precision.

SEND FOR COMPLETE DRILL CIRCULAR

JEVIN,,

LOUIS LEVIN & ty INC.
3573 Hayden Ave., Dept. E - Culver City, California

0.10mm to 3.00mm by 0.01mm increments

0.10mm to 0.70mm by 0.05mm increments

CIRCLE 204 ON READER SERVICE CARD

( SeMOR.
TOR

ELECTRONICS
ENGINEERS

NOW OPEN: TOP-LEVEL POSITIONS IN A TOP-LEVEL COMPANY
IN THE FIELD OF PRECISION MATERIALS TESTING...

Inventiveness and ingenuity are essential requirements for these
positions, and some mechanical experience would be helpful.
You will be designing electronic and electromechanical instruments
including analog and digital systems for the physical studies of
materials.

Some experience is required in general electronics, servo-
mech , transistor and relay circuitry, and transducers.
Opportunity to participate in a variety of interesting projects,
as well as introduce new concepts of instrumentation in the field
of materials testing.

About INSTRON and OPPORTUNITY...

Instron is an acknowledged front-runner in the field of instru-
mentation for precision materials testing. This is not only a
stimulating and exciting area — it is a growth field if there ever
was one. We choose our engineers with care, and when we've
found the right man we do everything in our power to make him
want to stay. If you're looking for a chall g and rewarding
opportunity, CALL 828- 2500 OR SEND YOUR RESUME TO
D. R. ERB.

INSTRON-

ENGINEERING CORPORATION
2500 Washington St., Canton, Massachusetts

EMPLOYMENT OPPORTUNITIES

electronics

WEEKLY QUALIFICATION FORM
FOR POSITIONS AVAILABLE

ATTENTION:
ENGINEERS, SCIENTISTS, PHYSICISTS

This Qualification Form is designed to help you advance in the elec-
tronics industry. It is unique and pact. Designed with the assistance
of professional personnel g t, it isolates specific experience
in electronics and deals only in essential background information.

COMPANY SEE PAGE

EITEL-McCULLOUGH, INC. §s* 1
San Carlos, California

ERIE ELECTRONICS DIVISION 75 2

The advertisers listed here are seeking professional experience. Fill in pay eines turn.

the Qualification Form below. F :
Erie, Pennsylvania

STRICTLY CONFIDENTIAL

Your Qualification form will be handled as “Strictly Confidential” by
ELECTRONICS. Our processing system is such that your form will be
forwarded within 24 hours to the proper executives in the companies

you select. You will be contacted at your home by the interested
companies.

ESQUIRE PERSONNEL SERVICE, INC.
Chicago, Illinois

GPL DIVISION

General Precision Inc.

Pleasantville, New York

INSTROM ENGINEERING CORP.
Canton, Massachusetts

WHAT TO DO

- Review the positions in the advertisements.

. Select those for which you qualify.

. Notice the key numbers.

. Circle the corresponding key ber below the Qualification Form.

. Fill out the form completely. Please print clearly.

. Mail to: D. Hawksby, Classified Advertising Div., ELECTRONICS,
Box 12, New York 36, N. Y. (No charge, of course).

MICROWAVE SERVICES INTERNATIONAL INC. 75 6
Denville, New Jersey

* These advertisements appeared in the 12/22/61 issue.

ounhoans

(cut here) (cut here)
nae electronics WEEKLY QUALIFICATION FORM FOR POSITIONS AVAILABLE
Personal Background Education
cer tis SO ns neds eke welidke hekanets amine oe ste tcc cc OI TE CE ES
ID 58 Sc ed Beran cain eee ee be omea eb ss og ME NN vetoatecicesnsiacd cess adtctie + eekeanewacds
I os hws cases «ince mE... ee ee NES ook. cade Aewee as ak ee. ei a ed
I ee eh. 5 4 te rh en fet hie rh ge i ened eae te Be Sly eof
FIELDS OF EXPERIENCE (Please Check) _ Se eee
Please indicate number of months
“ experience on proper lines.
CT] Aerospace TC] Fire Control CT Radar Technica ieee
x E i
C Antennas CJ Human Factors CT Radio—TV (Months). (Months)
RESEARCH (pure, ,
[lasw yo _] simulators fundamental, basic) ...... — ......
RESEARCH
CJ Circuits CJ Instrumentation CJ Solid State DE) i pwwear: peeps
SYSTEMS
ie Communications ie Medicine TC) Telemetry nr a ee
DEVELOPMENT
ge Components C] Microwave Cc] Transformers (Medel) $j§=—=—= = cescce cevvee
DESIGN
7 Computers & Navigation ‘a eer (Product) eens eka oa
MANUFACTURING
Tj ECM CT Operations Research i b obese bh wiles wis Oud ore eee, |< rt! UN ae
FIELD
‘a Electron Tubes a Optics Cc cee cere career eeens OS i? 2 ee rrr age eS
SALES
C) Edgineering Writing C) Packaging C] ee Peer ee (Proposals & Products) ......__......

CIRCLE KEY NUMBERS OF ABOVE COMPANIES’ POSITIONS THAT INTEREST YOU
S:2.53 628 67F 86 ORMNHMRBnewt Tr ewe eae Hh ee ae OS

74

electronics

Method for EMPLOYMENT OPPORTUNITIES
measuring The Advertisements in this section include all employ it oppor

tive, t, technical, selling, office, skilled, manual, etc.

an en ineer Positions Vacant Civil Service Opportunities Employment Agencies
g see Positions Wanted Selling Opportunities Wanted Employment Services
Part Time Work Selling Opportunities Offered Labor Bureaus

DISPLAYED ———RATES——— UNDISPLAYED
What's his

The advertising rate is $40.17 per inch for all adver- $2.70 per line, minimum 3 lines. To figure advance
tising appearing in other than a contract basis payment count 5 average words as a line.

technical Contract rates quoted on request. Bes }umbere—counte os 1 fie

An advertising inch is measured %” vertically on a
column—3 columns—-30 inches to a page.

publication CJ Subject to Agency Commission.

Send NEW ADS to CLASSIFIED ADV. DIV. of ELECTRONICS, P.O. Box 12, N. Y. 36, N. Y.

To evaluate closed circuit TV equip-

ment designed and manufactured by

the company. This involves design of
test equipment, preparation of test procedures and review of test data.

Discount of 109% if full payment is made in advance
tor 4 consecutive insertions.

Not subjeet to Agency Commission.

Education: equivalent of EE degree required. Must have 2-3 years experience in
operation and maintenance of studio or industrial TV equipment.

Please write or submit GPL DIVISION

resume indicating cur- GENERAL PRECISION. INC.

rent earnings to: Dp

Raymond L. Oakley. 63 Bedford Road, Pleasantville, N. Y.
An Equal Opportunity Employer

COMMUNICATIONS APPLICATION ENGINEER
TRANSFORMER ENGINEER Prey me Raper cactvonis ae regen coe sys-
tems including radio, carrier, telephone, microwave:
With experience in the design and devel- a - Must have design and marketing ox:
opment of Hi-Frequency and Pulse trans- Se
formers for commercial and military ap- ple ya
plications. Microwave Services International Inc.

- Ideal opportunity for ambitious man to UP . Consulting —— ;
When an engineer pays develop full potential of p t small de- — ———

for a technical publica- partment. Salary—open. Location—Erie,
tion, it’s a safe bet that Pa. Call or send resume to Chief Engineer SEARCHLIGHT
that is the one he respects Erie Electronics Division SECTION

most. Erie Resistor Corporation eee

645 West 12th Street Erie, Pa. : ;
GL 6-8592 . : /S or RESALE

He makes it his business DISPLAYED RATE

to read electronics. It FOR INFORMATION | | west sseet S202 or ae
keeps him well informed About Classified Advertising quoted. on” request. AN ADVERTIS-
of up 4 to the . minute Contact The McGraw-Hill - ally a yt. pos on , aieaee ae
events and developments Office Nearest You WANTED or FOR SALE SBVERTISE.
in the electronics indus- ATTS75 Peachtree St. WE gg Thinity 5-0523 a
try and ihe technology to ae Fa COngress 2-1160 $2.70 a on Glee sonnei figure
which he contributes his ima OO advance payment count 5 average words
experience. chevetago ape 2. MIGGERS ieee i coe nenen ue ceaet a6 one tar o0

1164 Iluminating =e ons SUperior 1-7000 neta B a eh ~ nae

o DALLAS, 2 made in advance for four consecutive
Where your recruitment ie ‘Commerce St., Vesene Bde. Riverside 7-5117 insertions of ispl: j

undisplayed ads (not in
z saneee. « cluding proposals)
program calls for engl- 1700 ‘Broadway—Tower | Bldg. Alpine 5-2981
neers and other technical DETROIT, 2 4

le of thi lib ; 2 856 Penobscot Bldg. WOodward 2-1793 SPECTRUM ANALYZERS
people of this calibre, you mute. * OOS Vectron Mod. SA25 with 20 LI Plug in
can reach them in the EM- Prudential Bidg., Holcombe Bivd., Rm. W-724 head—Freq. 800-2400 MC $895.00 com-

cKS

PLOYMENT OPPOR- J. PAGE plete. used, good cond.

- ANGELES, 17
TUNITIES section of: 1125 W. 6th St. HUntley 2-5450 BEACON ELECTRONICS

W. C. GRIES 1226 S. 26th St. Phoenix 34, Arizona
NEW YORK, 36
500 Fifth Ave. — OXford 5-5959 CIRCLE 460 ON READER SERVICE CARD

T. W. BENDER - P "SOND

PHILADELPHIA, 3 FOR RENT:
Six Penn Center Plaza LOcust 8-4330

r=\ {-Yes! ronics errrecuene SULLIVAN - F. W. McCARTHY PATERSON. N. J. 1 st. Brk. 26.000 ft.

11.500" bsmt, spkid. Hi pressure stm.
x -1314

(is) A McGRAW-HILL PUBLICAT © "4 see pe aa RR siding, fenced yd, unrstd. Exc. cond.
JEfferson 5-4867

FR-8033, Electronics
FFICE BOX 12 NEW YOF 3 NEW YORK 255 California St. DOuglas 2-4600 oe dv iv > 2. N.Y. 36, N.Y
J. A. HARTLEY Class Adv. Div., P.O. Box 12, 5p 4 y

CIRCLE 461 ON READER SERVICE CARD
December 29, 1961 75

CLASSIFIED Al

SILTRONICS. INC.

CONTINUALLY ON THE MOVE...

}
L fee |

COPE
S

COMMERCIAL . MILITARY.
DESIGN
DEVELOPMENT . MANUFACTURING

Communications and electronics sys-
tems, subsystems and components in-
corporating modular construction, solid
‘state and/or vacuum tube circuitry and
printed wiring precision electro-
mechanical devices . . . shock and vi-

bration mountings.

|
|
. +
}
lhronics, Yne.
2231 SAW MILL RUN BLVD.

PITTSBURGH, PA. / TU 4-0711

76 CIRCLE 76 ON READER SERVICE CARD

INDEX TO ADVERTISERS

Audited Paid Circulation

Alloyd Electronics Corp. ........ eee |
American Machine & Foundry Co.,

Potter & Brumfield Div. She Aix 22
American Time Products, Div. of

Bulova Watch Company, Ine. 16
Arnold Engineering Co., The 3
Bell Telephone Laboratories 27
Centralab, The Electronics Div, of

Globe-Union Ine. 53
Clairex Corp. . oa 69
Colorado Dept. of Development 72
Cross Co., H. . 32
Daystrom Incorporated ............ a;
Delco Radio a 71
Electronic Instrument Co., Ine. (EICO) 64
Fairchild Semiconductor Corp. 10
Fuji Tsushinki Seiz o K.K. 68

Gardner-Denver
General Radio Co

Company R
2nd Cover

Gudebrod Bros. Silk Co., Inc g 57
Hewlett Packard Company 8, 9
Hitachi, Ltd ; 34
Instron Engineering Corp 73
International Electronic Research Corp 6
Kepco, Ine. we a3 55
Levin and Son, Inc., Louis 7
Melabs 5 26
Microswitch, Div. of Minneapolis

Heneywell! Reg. Co. a 24, 25
Minnesota Mining & Mfg. Co

Mincom Division i 36
Mitsumi Electric Co., Ltd. 64
Norton Company 5
PRD Electronics, Ine. 61
Pacific Semiconductors In 23
Polarad Electrenies Corp. 3rd Cover
Potter & B:umfield, Division o

American Machine & Foundry Co 29
*recision Instrument Co 31

Radio Corporation of America

4th Cover
Radio Materials Co. 63

electr

102,
. *,

y.
RP

Teas*

Audit Bureau
of Circulations

Audited Paid
JAMES T.

Raychem Corporation

Sarkes Tarzian Inc. ee eee
® Servo Corporation of America : 35
® Sierra Electronic Corp. ..

Siltronics, Ine 98 Wsalhe 76
Sperry Electronic Tube Div
Sperry Rand Corp ; i 1x, 19
Sprague Electric Co, .. ot 6 > 33
Tinnerman Products, Inc. ........ ‘ 7
@ Vitro Electronics ....... 65
@ Western Devices, Inc. 69

CLASSIFIED ADVERTISING
F. J. Eberle, Business Mgr.

EMPLOYMENT OPPORTUNITIES ... 75
EQUIPMENT
(Used or Surplus New)
a” 7 RRS Aa a ee ees ree 75
6.03.0 ek con Oa mune eiekc he? 75

INDEX TO CLASSIFIED ADVERTISERS

Beacon Electronics 75
Erie Electronics Div.

Erie Resistor Corporation.... 75
GPL Div., General Precision Inc. 75
Microwave Services International Inc. 75

® See Advertisement in the July 20, 1961 issue
of Electronics Buyers’ Guide for complete line of
products or services.

This index and our Reader Service Numbers are pub-
lished as a service. Every nrecaution is taken ‘o make
them accurate, but ELECTRONICS ascumes no
responsibilities for errors or omissions.

onics

Associated Business
Publications

Circulation

HAUPTLI

Advertising Sales Manager

R. S. QUINT:
Assistant Publisher
Business Manager

FRED STEWART:
Promotion Manager

B. ANELLO:
Marketing Service Manager

Buyers’ Guide and

RICHARD J. TOMLINSON:
Production Manager

GEORGE E. POMEROY:
Classified Manager

HUGH J. QUINN:
Circulation Manager

ADVERTISING REPRESENTATIVES

NEW YORK (36):

Donald H. Miller, Henry M. Shaw, George

F. Werner

500 Fifth Avenue, OXford 5-5959
BOSTON (16):

William S. Hodgkinson, Donald R. Furth

McGraw-Hill Building, Copley Square,

Congress 2-1160
PITTSBURGH (22):

David M. Watson

Four Gateway Center, Express 1-1314
PHILADELPHIA (3):

Warren H. Gardner, William J. Boyle

6 Penn Center Plaza, LOcust 83-4330
CHICAGO (11):

Harvey W. Wernecke, Robert M. Denmead

645 North Michigan Avenue, Mohawk 4-5800
CLEVELAND (13):

Paul T. Fegley

55 Public Square, Superior 1-7000
SAN FRANCISCO (11):

R. C. Alcorn

255 California Street, Douglas 2-4600
LOS ANGELES (17):

Peter S. Carberry, Ashley P. Hartman

1125 W. 6th St., Huntley 2-5450

DENVER (2):
J. W. Patten
Tower Bldg., 1700 Broadway, Alpine 5-2981
ATLANTA (9):
Michael H. Miller
1375 Peachtree St. N.E., Trinity 5-0523
HOUSTON (25):
Joseph C. Page, Jr.
Prudential Bldg., Holcomb Bivd.,
Jackson 6-1281
DALLAS (1):
Frank Le Beau
The Vaughn Bidg., 1712 Commerce St.
Riverside 7-9721
LONDON WI:
Dennis McDonald
34 Dover St.
FRANKFURT/Main:
Stanley R. Kimes
85 Westendstrasse
GENEVA:
Michael R. Zeynel
2 Place du Port

electronics

A
WORLD
WIDE
STANDARD
POLARAD
FIELD

RECEIVERS

MODEL FIM-2
1,000 to 10,000 me.

Hundreds of Polarad Calibrated Field Intensity Receiv- ... because the FIM-2 is an integration of two instru-
ers are in use today throughout the world. Why? ments in one, it is always available in your laboratory as

is ai , ; ee -ither a sensitive microwave receiver or an accurate sig-
... because the FIM series, in production since 1956, of- po scthomecomg e microwave receiver or an accurate sig
fers +ldb accuracy because of its self-contained signal se 7 .
yr Ve s rAY . .
generator. .. because UNIDIAL® tunes both the receiver and signal
... because the Model FIM-2 is the only single unit micro- generator simultaneously; and, the front-panel meter
wave system capable of measuring rf interference and indicates average, peak, slide-back peak or quasi-peak
susceptibility. It has been designed for measurements in value of rf signals, the Polarad of FIM-2 is the most
accordance with all military RFI specifications. convenient instrument in use today.
MODEL FIM 9 FEATURES MAIL eeeeeeceeeeeeeoeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

# POLARAD ELECTRONICS CORPORATION:
43-20 34th St., Long Isiand City 1, N. Y.

THIS
COUPON
FREQUENCY RANGE: 1 ge to 10 ge in 4 tuning units; 2 more tuning
units under development will extend frequency to 20 ge.
FREQUENCY DIAL ACCURACY: +1
SENSITIVITY: 20 microvolts
MAXIMUM RF INPUT: 8 volts
IMPULSE BANDWIDTH: 5 me
IMAGE AND SPURIOUS RESPONSE REJECTION: 60 db
OUTPUTS: Video, audio, recorder
SIGNAL GENERATOR OUTPUT POWER: 0.223 volts to 5 microvolts
(for susceptibility measurements)
SIGNAL ATTENUATION: 0 to 80 db in 1 db steps

=| POLARAD ©

SERVICE| Evectronics corporation

43-20 34th Street. Long Island City 1.N.Y

Please send me information and specifications on:
—) Model FIM-2 Calibrated Microwave

Field Intensity Receiver POLARAD
() Notes on Microwave Measurements m Lesapet

My application is

Name

Title Mail Station

Company

Address

SHES HSHSHEHOHSSESESHESSHSSESEESETESEETESE

City

Representatives in Principal Cities (See your yellow pages)

h
GLOSE LOOK

EATER”

and how |
RAUATALLES
you |

You are looking at a major advance in tube
technology. The filament at the right in this
special demonstration envelope is a new RCA
“Dark Heater”. The “Dark Heater” operates
at a temperature about 350°K below that of
the 1500 to 1700°K of a conventional heater
(left). Yet at this much lower temperature,
the “Dark Heater” can produce the same cath-
ode temperature as the conventional heater.
Reason: the superior thermal emissivity of the
dark coating.

For additional information on the ‘Dark
Heater’’ call your RCA Field Representative or
write Commercial Engineering, Sec. L-19-DE-5,
RCA Electron Tube ivision, Harrison, N. J.

EAST: 744 Broad Street, Newark 2, New Jersey,
HUmboldt 5-3900 - MIDWEST: Suite 1154, Mer-
chandise Mart Plaza, Chicago 54, Illinois, WHite-
hall 4-2900 - WEST: 6801 E. Washington Bivd., Los
Angeles 22, Calif., RAymond 3-8361

The cooler operating “Dark Heater”
offers many receiving tube advantages to
equipment manufacturers, including:

e Longer heater life—because of the in-

herently greater tensile strength of heater

wire at lower temperatures.

e Reduced chance of heater failure—
because the smaller thermal change during heater cycling and the greatly
reduced operating temperatures minimize tendency toward recrystallization
and burnout.

e Heater-current stability on life—especially desirable in maintaining a
constant cathode temperature.

e Reduced AC heater-cathode leakage and hum—due to elimination of
“spike” or pulse leakage currents.

e Greater safety factor in established heater-cathode voltage ratings
e Improved mechanical stability—cooler operation of the “Dark Heater”
minimizes changes in heater shape during life, reducing the possibility of
heater damage and heater shorts.

The revolutionary “Dark Heater” is the key to improved performance and
longer life for receiving tubes. Now available in an increasing number of
RCA receiving tubes, the “Dark Heater” will be incorporated in those RCA
receiving types where potential benefits of increased life and reliability can
be realized.

The Most ‘Trusted Name in Electronics
®